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Flasher relay


Will

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Good news!  From the FSM, if you have a column shift, you only have one smart stick.  AND, you can change it by just removing the covers on the steering column and removing two screws.

Whoops, when I looked at removing the steering column covers, the first step is pulling the steering wheel.  This requires that you also remove the tilt lever and the knee bolster.

Removing the steering wheel begins with disabling the air bags and removing the air bag module.  The air bag module basically contains a small bomb, and it's dangerous to mess with, so we must take this step very seriously.  The air bag module is released by finding the access holes on either side of the steering wheel and using a tool to press release buttons in them.

Even though the good news is that you don't have to mess with the steering position sensor and its calibration, the tilt and telescoping motors, etc. etc. etc., it's still a bit of a job.  I would make sure that the multifunction switch is the problem with electrical testing before I did this job.

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-- Click Here for CaddyInfo page on "How To" Read Your OBD Codes
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13 minutes ago, Will said:

Yeah my hi beams and wipers are on the same stick along with my turn signals. Neither turn signals or high beams work only the wipers. Im feeling like its maybe in the switch but it confuses me why the wipers still function properly

That's a very good question, which is why I think checking the electrical things first, before you disable the air bags and pull the steering wheel, is a good idea.  The FSM doesn't help me here and I don't have a car to look at handy, but it may be that the wiper stuff is in the stalk itself near the end, and the turn signals and headlight switch stuff is in the box at the base of the stalk.  But I don't know.  @OldCadTech  or others like @BodybyFisher might know better; they have very likely changed the smart sticks on mid-2000's DTSs before.

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-- Click Here for CaddyInfo page on "How To" Read Your OBD Codes
-- Click Here for my personal page to download my OBD code list as an Excel file, plus other Cadillac data
-- See my CaddyInfo car blogs: 2011 CTS-V, 1997 ETC
Yes, I was Jims_97_ETC before I changed cars.

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Rather lengthy page in the GM service manual about the headlight malfunction. This is the service info for a 2006 DTS.

 

Headlamps Malfunction 
Diagnostic Instructions
    •  Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure 

    •  Review Strategy Based Diagnosis for an overview of the diagnostic approach 

    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category 

Diagnostic Fault Information
Circuit
 Short to Ground
 Open/High Resistance
 Short to Voltage
 Signal Performance
 
Low Beam Headlamp Supply Voltage
 1
 1
 3
 --
 
High Beam Headlamp Supply Voltage
 2
 2
 4
 --
 
Headlamp Low Beam Relay Control
 1
 1
 B2575 00
 --
 
Headlamp High Beam Relay Control
 2
 2
 B2580 00
 --
 
Headlamp Switch Headlamps Off Signal
 B257A 00
 6
 6*
 --
 
Headlamp Switch Headlamps On Signal
 B257A 00
 1
 1*
 --
 
Flash to Pass Switch Signal
 4
 5
 5*
 --
 
Headlamp Dimmer Switch High Beam Signal
 4
 2
 2*
 --
 
Low Beam Headlamp Ground
 --
 1
 1
 --
 
High Beam Headlamp Ground
 --
 2
 2
 --
 
Headlamp Switch Ground
 --
 1, 2
 1, 2
 --
 
Turn Signal/Multifunction Switch Ground
 --
 2, 5
 2, 5
 --
 
* Internal damage to the switch may occur if shorted to B+

Low Beam Headlamp(s) Inoperative 
High Beam Headlamp(s) Inoperative 
Low Beam Headlamp(s) Always On 
High Beam Headlamp(s) Always On 
Flash to Pass Inoperative 
Headlamp Defeat Inoperative 
 

Circuit/System Description
The vehicle headlamps are controlled by the body control module (BCM) based on inputs from the headlamp switch and the turn signal/multifunction switch. The headlamp switch has four positions: Off, Auto, Park, and Headlamps. The default headlamp switch position is Auto, in which the BCM uses the ambient light sensor to determine when headlamps are needed. The Off portion of the headlamp switch is a momentary switch which overrides the automatic headlamps and will turn off the vehicle headlamps. When in the Off position, the headlamp switch grounds the headlamp switch headlamps off signal circuit, prompting the BCM to turn off all exterior lamps. The Park position of the headlamp switch will only illuminate the vehicle parking lamps. The Headlamp position of the headlamp switch will illuminate both the parking lamps, as well has the headlamps. With the headlamp switch in the Headlamp position, the headlamp switch headlamps on signal circuit is grounded, prompting the BCM to turn on the headlamps, regardless of other factors such as ambient light.

The headlamp high beams are controlled through the flash to pass switch and the headlamp dimmer switch, both located in the turn signal/multifunction switch. The flash to pass switch is a momentary type switch, designed to illuminate the high beams as long as the switch is held. With the switch closed, the flash to pass switch signal circuit is grounded, prompting the BCM to turn on the high beam lamps. The headlamp dimmer switch allows the operator to select between full time high or low beam operation. Unlike the flash to pass switch, it is not a momentary switch. When the headlamp dimmer switch is in the high beam position, the headlamp dimmer switch high beam signal circuit is grounded. This prompts the BCM to turn on the high beam lamps.

The BCM controls the headlamps based on the inputs explained above. When a low beam request is received, the BCM grounds the headlamp low beam relay control circuit. This energizes the coil in the LO BEAM PCB Relay, causing the relay switch to close. This then applies B+ through the LT LO BEAM and RT LO BEAM fuses, the headlamp supply voltage circuits to the headlamp ballasts, illuminating the headlamps. When a high beam request is received, the BCM grounds the headlamp high beam relay control circuit. This energizes the coil in the HIGH BEAM PCB Relay, causing the relay switch to close. Battery voltage is then applied through both HI BEAM fuses and the high beam headlamp supply voltage circuits to the headlamp high beam solenoids. The solenoids then open the low beam shields to fully expose the headlamp bulbs for high beam operation.

Reference Information
Schematic Reference
Headlights/Daytime Running Lights (DRL) Schematics

Connector End View Reference
Lighting Systems Connector End Views

Description and Operation
Exterior Lighting Systems Description and Operation

Electrical Information Reference

    •  Circuit Testing 

    •  Connector Repairs 

    •  Testing for Intermittent Conditions and Poor Connections 

    •  Wiring Repairs 


Scan Tool Reference

    •  Scan Tool Output Controls 

    •  Scan Tool Data List 

    •  Scan Tool Data Definitions 


Circuit/System Verification
Ignition ON, observe the scan tool Auto Hdlp. Disable Sw. parameter while cycling the headlamp switch between the Auto and Off positions. The parameter should cycle between Active and Inactive. 
⇒ If the parameter does not cycle between the specified values, refer to Headlamp Switch Circuit Test. 

Observe the scan tool Headlamp Switch parameter while cycling the headlamp switch between the Auto and Head position. The parameter should cycle between Active and Inactive. 
⇒ If the parameter does not cycle between the specified values, refer to Headlamp Switch Test. 

With the headlamps ON, observe the scan tool Flash to Pass Switch parameter while pulling and releasing the flash to pass switch. The parameter should cycle between Active and Inactive. 
⇒ If the parameter does not cycle between the specified values, refer to Turn Signal/Multifunction Switch Test. 

With the headlamps ON, observe the scan tool High Beam Select Switch parameter while switching the headlamp dimmer switch between the low and high beam positions. The parameter should cycle between Active and Inactive. 
⇒ If the parameter does not cycle between the specified values, refer to Turn Signal/Multifunction Switch Test. 

Ignition ON, with a test lamp connected to ground, probe each of the test points on either LO BEAM Fuse while commanding the Low Beams ON and OFF with a scan tool. The test lamp should turn ON and OFF at one or both of the fuse test points when changing between commanded states. 
⇒ If the test lamp is always OFF, or remains always ON, refer to Low Beam PCB Relay Circuit Test. 

⇒ If the test lamp turns ON and OFF, refer to Headlamps Circuit Test 

Ignition ON, with a test lamp connected to ground, probe each of the test points on either HI BEAM Fuse while commanding the High Beams ON and OFF with a scan tool. The test lamp should turn ON and OFF at one or both of the fuse test points when changing between commanded states. 
⇒ If the test lamp is always OFF, or remains always ON, refer to High Beam PCB Relay Circuit Test. 

⇒ If the test lamp turns ON and OFF, refer to High Beam Circuit Test 

Ignition ON, headlamps ON, observe the high beam indicator on the IPC while cycling the high beam dimmer switch ON and OFF. The indicator should turn ON and OFF when changing between commanded states. 
⇒ If the indicator is always OFF or remains always ON, replace the IPC. 

Circuit/System Testing
Caution: The high intensity discharge system produces high voltage and current. To reduce the risk of severe shocks and burns: 

   •  Never open the high intensity discharge system ballast or the arc tube assembly starter. 

   •  Never probe between the high intensity discharge system ballast output connector and the arc tube assembly. 


Headlamp Switch Circuit Test
Ignition OFF, disconnect the harness connector at the headlamp switch. 
Ignition OFF, verify that a test lamp illuminates between the ground circuit terminal 8 and B+. 
⇒ If the test lamp does not illuminate, test the ground circuit for an open/high resistance. 

Ignition ON, verify the scan tool Headlamp Switch parameter is Inactive. 
⇒ If not the specified value, test the signal circuit terminal 1 for a short to ground. If the circuit tests normal, replace the BCM. 

Verify the scan tool Auto Hdlp. Disable Sw. parameter is Inactive. 
⇒ If not the specified value, test the signal circuit terminal 3 for a short to ground. If the circuit tests normal, replace the BCM. 

Install a 3A fused jumper wire between the signal circuit terminal 1 and ground. Verify the scan tool Headlamp Switch parameter is Active. 
⇒ If not the specified value, test the signal circuit for a short to voltage or and open/high resistance. If the circuit tests normal, replace the BCM. 

Install a 3A fused jumper wire between the signal circuit terminal 3 and ground. Verify the scan tool Auto Hdlp. Disable Sw. parameter is Active. 
⇒ If not the specified value, test the signal circuit for a short to voltage or and open/high resistance. If the circuit tests normal, replace the BCM. 

If all circuits test normal, test or replace the headlamp switch. 
Turn Signal/Multifunction Switch Circuit Test
Ignition OFF, disconnect the (C2) harness connector at the turn signal/multifunction switch. 
Ignition OFF, test for less than 5.0 ohms of resistance between the ground circuit terminal D and ground. 
⇒ If greater than the specified range, test the ground circuit for an open/high resistance. 

Ignition ON, verify the scan tool Flash to Pass Switch parameter is Inactive. 
⇒ If not the specified value, test the signal circuit terminal A for a short to ground. If the circuit tests normal, replace the BCM. 

Verify the scan tool High Beam Select Switch parameter is Inactive. 
⇒ If not the specified value, test the signal circuit terminal E for a short to ground. If the circuit tests normal, replace the BCM. 

Install a 3A fused jumper wire between the signal circuit terminal A and ground. Verify the scan tool Flash to Pass Switch parameter is Active. 
⇒ If not the specified value, test the signal circuit for a short to voltage or and open/high resistance. If the circuit tests normal, replace the BCM. 

Install a 3A fused jumper wire between the signal circuit terminal E and ground. Verify the scan tool High Beam Select Switch parameter is Active. 
⇒ If not the specified value, test the signal circuit for a short to voltage or and open/high resistance. If the circuit tests normal, replace the BCM. 

If all circuits test normal, test or replace the turn signal/multifunction switch. 
Low Beam PCB Relay Circuit Test
Ignition OFF, disconnect the (C2) harness connector at the underhood fuse block. 
Connect a test lamp between the control circuit terminal 10 and B+. 
Ignition ON, command the Low Beams ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. 
⇒ If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the BCM. 

⇒ If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM. 

If all circuits test normal, replace the underhood fuse block. 
Headlamps Circuit Test
Disconnect the harness connector at the inoperative headlamp assembly. 
Ignition OFF, test for less than 5.0 ohms of resistance between the ground circuit terminal F and ground. 
⇒ If greater than the specified range, test the ground circuit for an open/high resistance. 

Connect a test lamp between the supply voltage circuit terminal E and ground. 
Ignition ON, command the Low Beams ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. 
⇒ If the test lamp is always ON, test the supply voltage circuit for a short to voltage. If the circuit tests normal, replace the underhood fuse block. 

⇒ If the test lamp is always OFF, test the supply voltage circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the underhood fuse block. 

If all circuits test normal, test or replace the inoperative headlamp bulb. 
High Beam PCB Relay Circuit Test
Ignition OFF, disconnect the (C2) harness connector at the underhood fuse block. 
Connect a test lamp between B+ and the control circuit terminal 19. 
Ignition ON, command the High Beams ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. 
⇒ If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the BCM. 

⇒ If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM. 

If all circuits test normal, replace the underhood fuse block. 
High Beam Circuit Test
Disconnect the harness connector at the inoperative headlamp assembly. 
Ignition OFF, test for less than 5.0 ohms of resistance between the ground circuit terminal F and ground. 
⇒ If greater than the specified range, test the ground circuit for an open/high resistance. 

Connect a test lamp between the supply voltage circuit terminal D and ground. 
Ignition ON, command the High Beams ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. 
⇒ If the test lamp is always ON, test the supply voltage circuit for a short to voltage. If the circuit tests normal, replace the underhood fuse block. 

⇒ If the test lamp is always OFF, test the supply voltage circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the underhood fuse block. 

If all circuits test normal, test or replace the inoperative headlamp assembly. 
Component Testing
Headlamp Switch
Ignition OFF, disconnect the harness connector at the headlamp switch. 
Test for infinite resistance between the signal terminal 3 and the ground terminal 8 with the switch in the Auto position. 
⇒ If not the specified value, replace the headlamp switch. 

Test for infinite resistance between the signal terminal 1 and the ground terminal 8 with the switch in the Auto position. 
⇒ If not the specified value, replace the headlamp switch. 

Test for less than 2.0 ohms of resistance between the signal terminal 3 and the ground terminal 8 with the switch in the Off position. 
⇒ If not the specified value, replace the headlamp switch. 

Test for less than 2.0 ohms of resistance between the signal terminal 1 and the ground terminal 8 with the switch in the Headlamp position. 
⇒ If not the specified value, replace the headlamp switch. 

Turn Signal/Multifunction Switch
Ignition OFF, disconnect the (C2) harness connector at the turn signal/multifunction switch. 
Test for infinite resistance between the signal terminal A and the ground terminal D with the flash to pass switch in the open position. 
⇒ If not the specified value, replace the turn signal/multifunction switch. 

Test for infinite resistance between the signal terminal E and the ground terminal D with the headlamp dimmer switch in the low beam position. 
⇒ If not the specified value, replace the turn signal/multifunction switch. 

Test for less than 2.0 ohms of resistance between the signal terminal A and the ground terminal D with the flash to pass switch in the closed position. 
⇒ If not the specified value, replace the turn signal/multifunction switch. 

Test for less than 2.0 ohms of resistance between the signal terminal E and the ground terminal D with the headlamp dimmer switch in the high beam position. 
⇒ If not the specified value, replace the turn signal/multifunction switch. 

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The car is a 2006 DTS.  There are several DTCs, and if Will's code reader shows BCM codes, the fact that there aren't any eliminates the problems that throw codes.

Better to go through that and be sure where you are before you start taking things apart, than to change the smart stick, and then, if that doesn't fix it, to have to do it all anyway.

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-- Click Here for CaddyInfo page on "How To" Read Your OBD Codes
-- Click Here for my personal page to download my OBD code list as an Excel file, plus other Cadillac data
-- See my CaddyInfo car blogs: 2011 CTS-V, 1997 ETC
Yes, I was Jims_97_ETC before I changed cars.

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The info was looked up as a 2006 DTS.

On first glance....the service info shows the high beam relay is a pcb relay and is non serviceable...underhood fuse block. 

Pic of the switch

headswitch.jpg

pcbrelay.JPG

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I haven't really been following the diagnosis path with what has been covered etc. I was just providing info from the GM service manual.

Anyway....if the problem is a PCB relay.....it won't be just a easy part swap. I've heard of them....but have not had to work on any PCB fuseblocks. 

Here is a quick link I found about PCB fuseblocks....yikes...are glass BUSS fuses going the way of the buggy whip too?

http://www.ansys.com/about-ansys/advantage-magazine/volume-x-issue-1-2016/keeping-the-block-cool

 

 

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@Will did you verify that the mirror settings and the light switch were set properly?

@Cadillac Jim thanks for the FSM work :hatsoff:

Since there is a Left and Right high beam relay and neither hi-beam is lit, that screams ISRVM or BCM to me. Very hard to diagnose long distance. A tech2 is going to be a requirement for diag on the I-Beam.

The turn signals are a separate problem. Since there are No turn signals front or rear I would look for a fuse or wiring issue. I would think the multi-function switch would be a 3rd place suspect after fuses and wiring.

BUT, there is one common denominator for both problems and that is the BCM. AGAIN, a TECH2 is mandatory for that diagnosis.

Has there been ANY MODS including but not limited to electrical system mods, such as sound system enhancements, Amps, hydraulics or anything the factory did not install?

THERE IS ALWAYS ENOUGH TIME TO DO THE JOB RIGHT - THERE IS NEVER ENOUGH TIME TO DO THE JOB AGAIN !!!

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I see only one HI BEAM relay for both sides, but it powers two separate fuses, one fuse for each side.  I do see a note on the schematic, "PCB relay," now that Logan points that out.  The fact that it's not a throwaway means to me that it might be a "solid state relay" that uses a type of IGFET with an optical isolator, with the "coil" being an LED and the gate of the IGFET being controlled by a photocell.  The LED and photocell are pieces of an opto-electric isolator.  These relays are a lot more expensive than mechanical relays but they very rarely go bad.  In any case, I would expect that any relay that they put on a non-serviceable PC board is not a go-to replacement item for a failure, like a mechanical relay in a socket.

In other words, I think Logan has eliminated the headlight relay as a likely candidate for the problem with the high beams.

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-- Click Here for CaddyInfo page on "How To" Read Your OBD Codes
-- Click Here for my personal page to download my OBD code list as an Excel file, plus other Cadillac data
-- See my CaddyInfo car blogs: 2011 CTS-V, 1997 ETC
Yes, I was Jims_97_ETC before I changed cars.

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WOW! I posted and all of a sudden there are 15 posts I didn't see before.

It's okay though, what @Logan posted only supported what I said :paint2:

Again, check for aftermarket add-ons or mods of anything.

THERE IS ALWAYS ENOUGH TIME TO DO THE JOB RIGHT - THERE IS NEVER ENOUGH TIME TO DO THE JOB AGAIN !!!

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I knew it couldn't be a normal relay to control the headlamps. Didn't make sense, I wasn't expecting a PCB either though. :mellow:

THERE IS ALWAYS ENOUGH TIME TO DO THE JOB RIGHT - THERE IS NEVER ENOUGH TIME TO DO THE JOB AGAIN !!!

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8 minutes ago, Cadillac Jim said:

"solid state relay" that uses a type of IGFET with an optical isolator, with the "coil" being an LED and the gate of the IGFET being controlled by a photocell.  The LED and photocell are pieces of an opto-electric isolator. 

That photocell would be in the ISRVM & I bet the coil is the switch LED in the ISRVM. Which brings me back to the question - was the LED illuminated on the mirror with the switch in the on position.

THERE IS ALWAYS ENOUGH TIME TO DO THE JOB RIGHT - THERE IS NEVER ENOUGH TIME TO DO THE JOB AGAIN !!!

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As if the waters weren't cloudy enough I discovered this in the Owners manual....

(Stalk Disable): When Intellibeam™ has turned on the high-beams, pull or push the high-beam stalk. This will disable Intellibeam™. The Intellibeam™ indicator on the mirror will turn off. To re-enable Intellibeam™, press the Intellibeam™ button on the mirror.

Is the turn signal "Stalk" sloppy?

THERE IS ALWAYS ENOUGH TIME TO DO THE JOB RIGHT - THERE IS NEVER ENOUGH TIME TO DO THE JOB AGAIN !!!

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Solid-Relay-40A-SSR-40DD.jpgSolid-State-Relay-1024x536.jpg

CTS-V_LateralGs_6-2018_tiny.jpg
-- Click Here for CaddyInfo page on "How To" Read Your OBD Codes
-- Click Here for my personal page to download my OBD code list as an Excel file, plus other Cadillac data
-- See my CaddyInfo car blogs: 2011 CTS-V, 1997 ETC
Yes, I was Jims_97_ETC before I changed cars.

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There are two illuminations in the hazard warning switch:  the dashboard illumination, which is a bulb that is powered by the dimmed dashboard power and is part of the dash lighting, and an LED that turns on when the hazard warning lights are active.

The bulb in the Hazard Warning Switch is powered by the dimmer power for the dashboard.  It's brightness is controlled by the interior light dimming.  If the car sees daylight in the dashboard ambient light sensor under the rearview mirror at the front center of the dashboard, the lights aren't dimmed.  If you put a clipboard over that sensor and wait a few seconds, or at night, the dash and interior lights are dimmed, and you have a control near the headlight switch to control the amount of dimming.  If that works, there is no reason that the hazard warning switch illumination should not work too.

The LED, which is a lot brigher than the dashboard illumintion bulb, is in the same circuit as the signal to the BCM, a TN (probably tan) wire between the switch and the BCM.  If it doesn't light, then either the hazard warnign switch is not connected to the BCM, or the BCM is not powering the switch circuit.

Any connection between the hazard warning switch and anything else in the car is through the BCM logic.  There is no physical connection between the hazard warning switch and anything other than the BCM (except the dashboard illumination bulb).  EXCEPT:  the tan wire is on the same conector as the turn signal wires to the BCM, C1, which is a 27-terminal GN (green) connector on the BCM.  From my SI DVD:

Untitled 1.rtf

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-- Click Here for CaddyInfo page on "How To" Read Your OBD Codes
-- Click Here for my personal page to download my OBD code list as an Excel file, plus other Cadillac data
-- See my CaddyInfo car blogs: 2011 CTS-V, 1997 ETC
Yes, I was Jims_97_ETC before I changed cars.

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