Jump to content
CaddyInfo Cadillac Forum

Traction Control - Service Stability System- ABS


Recommended Posts

I have lights and warnings that have been intermitent inthe past and are now on full time.

I am getting error codes

ABS C1242,C1253

Also

RSS C1711,C1726,C1783,C1782,C1785

Anybody have an idea of what I should look at first

Link to comment
Share on other sites


I have lights and warnings that have been intermitent inthe past and are now on full time.

I am getting error codes

ABS C1242

C1242 - Pump Motor Circuit Open

This refers to the motor circuit that drives the pump in the ABS module to supply brake pressure for traction control purposes. The problem might be as simple as a broken or corroded chassis ground wire from the motor case to the vehicle chassis.

C1253
C1253 - Right Front Normal Force Malfunction

This is a calculation error that will go away when all the error codes are corrected.

C1711
C1711 - Left Front Damper Actuator Short Circuit to Ground
C1726
C1726 - Right Rear Damper Actuator Short Circuit to Ground

Worst case would be LF strut and RR shock solenoid coils have failed internally. Not very likely. First and foremost always double check the wire harness that connects the strut and shock to the chassis harness looking for damage and/or corrosion.

If you are handy with electronic parts testing, you can susbstitute a 4.7K Ohm resistor for each of those two solenoids as a test.

C1783,C1782,C1785

C1782 - ICCS2 DL Left Output Short Circuit to Bat

C1783 - ICCS2 DL Left Output Short Circuit to GND

C1785 - ICCS2 DL Right Output Short Circuit to GND

These codes are also calculations and will go away when you repair the strut and shock condition.

If this car has lived in the snow belt, I would suspect major electrical connector corrosion issues. Have there been any major repairs made to the car recently? Such as engine removal or collision damage repair?

Jim

Drive your car.

Use your cell phone.

CHOOSE ONE !

Link to comment
Share on other sites

Jim, Thanks for the reply,

It has never seen the snow- but we are in Texas and have to deal with heat. It has never been in any accidents or had major work done.

The only annoying issue I have had has been an oil leak that I have had for a number of years and have recently been told that this can be the source of many problems if not taken care of. (Oil tends to get around underneath)

Can you tell me where the C1242 - Pump Motor is located on the car so I can check the circuit?

Paul

Link to comment
Share on other sites

Jim, Thanks for the reply,

It has never seen the snow- but we are in Texas and have to deal with heat.

Corrosion could still be a problem IF you live along the Gulf coast.
The only annoying issue I have had has been an oil leak that I have had for a number of years and have recently been told that this can be the source of many problems if not taken care of. (Oil tends to get around underneath)
Oil spray is not responsible for the codes you mentioned. The underside of my '98 is oil coated all the way back to the rear suspension components and in 13 years and 206,xxx miles, I have never had a code that was caused by oil spray.
Can you tell me where the C1242 - Pump Motor is located on the car so I can check the circuit?
Bottom left front corner of the engine cradle, easily identified by the six steel brake lines attached. The complete assembly is known as the Electronic Brake and Traction Control Module (EBTCM).

Jim

Drive your car.

Use your cell phone.

CHOOSE ONE !

Link to comment
Share on other sites

Jim, Thanks for the reply,

It has never seen the snow- but we are in Texas and have to deal with heat.

Corrosion could still be a problem IF you live along the Gulf coast.
The only annoying issue I have had has been an oil leak that I have had for a number of years and have recently been told that this can be the source of many problems if not taken care of. (Oil tends to get around underneath)
Oil spray is not responsible for the codes you mentioned. The underside of my '98 is oil coated all the way back to the rear suspension components and in 13 years and 206,xxx miles, I have never had a code that was caused by oil spray.
Can you tell me where the C1242 - Pump Motor is located on the car so I can check the circuit?
Bottom left front corner of the engine cradle, easily identified by the six steel brake lines attached. The complete assembly is known as the Electronic Brake and Traction Control Module (EBTCM).

Link to comment
Share on other sites

Jim- have dug into tis yet but is this accessible from under the hood- or am I going to need a lift, or maybe access it from the wheel well

Under the hood will not work. My first choice would be to lift the front end far enough to remove the plastic air deflector panel that covers the bottom from the bumper cover to the front edge of the engine cradle (Rhino Ramps give me another 6.5" to work with; I use them all the time for oil/filter changes).

You might be able to get in there through the wheel well but I have never done that.

Jim

Drive your car.

Use your cell phone.

CHOOSE ONE !

Link to comment
Share on other sites

Jim- have dug into tis yet but is this accessible from under the hood- or am I going to need a lift, or maybe access it from the wheel well

When I repaired mine on my 2003 DTS I accessed it through the top and through the LH wheel well. Ultimately the problem with my EBTCM I had to re-solder the pins on the relay inside. This involved opening the EBTCM up, which was difficult because it is filled with silicone sealent.

OldFart

Link to comment
Share on other sites

Jim- have dug into tis yet but is this accessible from under the hood- or am I going to need a lift, or maybe access it from the wheel well

Under the hood will not work. My first choice would be to lift the front end far enough to remove the plastic air deflector panel that covers the bottom from the bumper cover to the front edge of the engine cradle (Rhino Ramps give me another 6.5" to work with; I use them all the time for oil/filter changes).

You might be able to get in there through the wheel well but I have never done that.

Link to comment
Share on other sites

Jim/Old Fart

I finally dug into this yesterday.

I removed the wiring harness- inspected the pins, removed the ground wire cleaned it, ultimately I did not find any issues or corrosion. I put it back together. Cleared the codes, and no change to the warning lights. In fact I noticed the warning lights went on even without engaging the ignition- just turning the key.

Got any other suggestions. Any way to test the circuits in this module without removing it. It looks challenging to remove.

Link to comment
Share on other sites

The C1242 is pointing to the pump circuit and it is an intregal part of the BPMV (the part that has the brake lines going into it) and is not serviceable by itself. If you are proficient with a DVM you could meter the leads from the pump itself to confirm it is defective before replacing. Your FSM has a schmatic for the entire circuit. It does not sound like the EBTCM itself is defective, although that does control the pump.

OldFart

Link to comment
Share on other sites

I was fianlly able to look at this and I was able to fix it. Turns out the EBTCM ground line was not grounded. I cleaned it up and not works great.

I am now on to my second issue. The RSS C1711,C1726 codes. Codes tell me that there is some sort of a short to ground. I have checked the circuit from the Damper Actuator all the way to the unit mounted behind the passenger seat. Nothing looks shorted to ground,and I seem to be getting the correct resistance across the solenoid 13.1 ohms. Anyone have an additional suggestions? Should I replace the CVTX module behind the seat. How much do you think it is?

Link to comment
Share on other sites

I was fianlly able to look at this and I was able to fix it. Turns out the EBTCM ground line was not grounded. I cleaned it up and not works great.

Quite a difference from what you reported in post #11.
I am now on to my second issue. The RSS C1711,C1726 codes. Codes tell me that there is some sort of a short to ground. I have checked the circuit from the Damper Actuator all the way to the unit mounted behind the passenger seat. Nothing looks shorted to ground,and I seem to be getting the correct resistance across the solenoid 13.1 ohms. Anyone have an additional suggestions? Should I replace the CVTX module behind the seat. How much do you think it is?

You might try what I suggested about substituting resistors as a test in post #2. If you have considerable electronic skills/experience, there is a chance that one or more of the voltage sensing resistors in the CVRSS module have burned open. After removing and opening the module, the damage would be visibly obvious. But you will be in surface mount technology territory and proper soldering tools/skills/experience are necessary/mandatory. The SMT resistor value is 1K Ohm.

Jim

Drive your car.

Use your cell phone.

CHOOSE ONE !

Link to comment
Share on other sites

It is amazing what a $5 can of contact cleaner and a tooth brush can do for electical connections. I didn't put much stock into it at first - but after I got the terminals nice and shiny - it worked like a champ. I guess 12 years of Texas heat can effect a vehicle after all! Thanks for the advice- I will break open the module

Link to comment
Share on other sites

I was fianlly able to look at this and I was able to fix it. Turns out the EBTCM ground line was not grounded. I cleaned it up and not works great.

Quite a difference from what you reported in post #11.
I am now on to my second issue. The RSS C1711,C1726 codes. Codes tell me that there is some sort of a short to ground. I have checked the circuit from the Damper Actuator all the way to the unit mounted behind the passenger seat. Nothing looks shorted to ground,and I seem to be getting the correct resistance across the solenoid 13.1 ohms. Anyone have an additional suggestions? Should I replace the CVTX module behind the seat. How much do you think it is?

You might try what I suggested about substituting resistors as a test in post #2. If you have considerable electronic skills/experience, there is a chance that one or more of the voltage sensing resistors in the CVRSS module have burned open. After removing and opening the module, the damage would be visibly obvious. But you will be in surface mount technology territory and proper soldering tools/skills/experience are necessary/mandatory. The SMT resistor value is 1K Ohm.

I love surface mount soldering. Very few know how to solder and even fewer solder surface mount. Makes me feel special... :)

Caddy_Grill.jpg2008 DTS
Link to comment
Share on other sites

I love surface mount soldering. Very few know how to solder and even fewer solder surface mount. Makes me feel special... :)

Put me in the group that knows how to solder with 50+ years experience soldering everything from copper plumbing to delicate PCBs.

But I disqualify myself for SMT work because of my "old" eyes and unsteady hands.

Jim

Drive your car.

Use your cell phone.

CHOOSE ONE !

Link to comment
Share on other sites

So I have traced through the circuits on all four wheels and even tried swaping soleniods- using long leads between each wheel. I am still getting shorts to grounds on each of the RR and LF wheels, even with the known good soleniods hooked into the bad circuits.

I used a 4.7K ohm resistor on the RR and LF - same issue. (It was actually a 4.79K ohm does that matter?)

I have taken appart the module and tested the circuits as best I can- and I am getting NO shorts to gound readings using a DMM. I am also getting the exact same readings at each pin set for each wheel- all the same readings between the pin and ground (readings in the high OHM range), which tells me the input circuits on the PCB module seem to be OK.

I saw no damage or burnt resistors after looking at the circuit board with a magnifying glass.

Is my last hope to spend money on the module?

How much are these CVRSS modules? anyone know?

Link to comment
Share on other sites

So I have traced through the circuits on all four wheels and even tried swaping soleniods- using long leads between each wheel. I am still getting shorts to grounds on each of the RR and LF wheels, even with the known good soleniods hooked into the bad circuits.

I used a 4.7K ohm resistor on the RR and LF - same issue. (It was actually a 4.79K ohm does that matter?)

The actual measured value of the resistor is not critical but that is a poorly manufactured resistor or your Ohmmeter is less than accurate. Common carbon resistor values are stated in no more than two significant digits.

Still getting "short to ground" codes after all your steps (and well done for the time and effort to do all that) leaves me with two prime suspects. First would be a damaged wire harness somewhere. Has the engine cradle been removed and installed lately? Any recent collision damage repair?

Second would be the module. But I would invest a lot of time on the first suspect before I replaced the module.

Jim

Drive your car.

Use your cell phone.

CHOOSE ONE !

Link to comment
Share on other sites

I used a 4.7K ohm resistor on the RR and LF - same issue. (It was actually a 4.79K ohm does that matter?)

I have taken appart the module and tested the circuits as best I can- and I am getting NO shorts to gound readings using a DMM. I am also getting the exact same readings at each pin set for each wheel- all the same readings between the pin and ground (readings in the high OHM range), which tells me the input circuits on the PCB module seem to be OK.

You can use your DVM to verify the resister is 4.79k, it should be spot on (depending on the tolerance of the resister which is usually stamped on the package)

As for the short to ground, high resistance is a short to ground. Let me clarify, with your DVM on and in the OHMS position hold the leads out in front of you and do not touch them to anything. The resistance should be infinite (my DVM reads OL), the same reading when you are probing the circuits if there is no short to ground. Also, the circuit should be isolated - not connected at either end. If either end is connected you will be reading the internal resistance of whichever end is connected, the solenoids or the control module, which is giving you a false reading. To recap, disconnect the module and the solenoids and then re-check for shorts to ground.

Edited by OldFart

OldFart

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...