Car Wont Start

[alvarado626]

Hi Guys Hope Someone will help me out on this one

a month a go I decided to Change the Turn signal Switch on My 98 Deville

When I finished Car Didn't Start its Giving Current Codes B2750 and B2711

B2750 passlock data comunication failure no start

B2711 Passkey open/shorted pellet after good key

Now I Have Changed Ignition Switch and new key

I Tried the Resistor bypass thing no luck

at this point i have removed the Dash top disconnected the Cluster and measure resistance wires coming from connector terminal (E12)WhiteBlack wire and (E13)Purplewhite wire I'm Still getting the same value pallet as the new key

I Towed the car to the dealer it was $$130.00 to perform a diagnostic Guy In Service called me the next day

He told me that they need to go deeper to c whats wrong with the car

he mentioned to remove the dashboard to check in the cluster he gave me a cost estimate starting at $$$700.00 dollars and so on..... I called AAA and towed my car back Home Just to found out all i need was to remove 7 bolts to get to the Cluster

Now as soon as i place the key in the ignition switch the SECURITY Light start Blinking

Does any one Can Help me out on how to know if cluster its fry or am i looking in the wrong place i cant afford the dealer at this time THANK U IN ADVANCE

[Cadillac Jim]

For one thing, B2711 just means that the connection to the resistor pelliet is a little flaky. Usually you just need to clean the key and make sure that no lint has found its way into the keyhole.

B2750 may mean that something was left unplugged. It doesn't mean that something is bad.

I would start by putting everything back together and starting over.

[alvarado626]

Hi Key and Ignition switch r 2 weeks old

as soon as it stops from Raining i work on that Thank u Jim

[alvarado626]

Also my Key # is 13 Wish Means My Resistance its 7500 Ohms same reading as the cluster plug

[BodybyFisher]

Review this link someone else is having a similar problem right now

http://caddyinfo.ipbhost.com/index.php?showtopic=38191&st=0

[alvarado626]

I Already check Fuel Pressure and also sparks its all good Thx Fisher

[BodybyFisher]

I Already check Fuel Pressure and also sparks its all good Thx Fisher

That is a lot more to that thread, you both have the B2750, pop into that thread and check it once in a while

[alvarado626]

Thx Fishes I Keep an Eye on that

Only Difference is Hes B2750 is History and mine is Current

[Cadillac Jim]

Any CURRENT code means that there is an ongoing problem. CURRENT codes should be addressed first.

[WarrenJ]

It sounds like the Body Control Module (aka BCM or PZM (Platform Zone Module)) is not communicating properly. I would expect that if one of the several fuses associated with the PZM were blown, a DTC would be set. But hey, you never know . . .

Have you checked ALL of the engine compartment and trunk compartment fuses?

I know . . . it's a long shot.

[alvarado626]

Yes I did Check all fuses But I'll Double Check This Morning Thx Jim and Warren

[alvarado626]

OK Now that I Cleaned Up and Replace with a New Battery

Now PZ2255 is CURRENT If I Get a Used or New BCM do i have to reprogram that module at the Dealer ?

Also Forget to Mention my Car 's Engine Turns But it Wont Start

Thank u Guys for Taking to time to Help ...........

[Cadillac Jim]

The fact that it's setting that code probably prevents the PCM from turning on the fuel pump or injectors.

From Bodybyfisher's post on that code, it seems to be more likely a software problem than a bad module, or at least perhaps that should be looked at. I would reset the codes from the A/C console and try again before I bought anything. Maybe even disconnecting the battery for five minutes so that all the modules reset would help.

[alvarado626]

Ok Heres My Last Up dated I Cleared all Codes Again and PZ1255 is Now History

I Only Have B2750 AND 2711 Currents

By This Time I'm All Confuse what to do Next Thank u

[Cadillac Jim]

B2750 PASSKey Data Communication Failure

B2711 PASSKey Open/Shorted Pellet After Good Key

I would address B2711 first, and I think it's possible that B2750 is a result of the IPM asking too many things of the PZM too quickly because it's getting a flood of software-direction actions and sending resulting messages because of a scratchy connection to the resistor in the key.

Some people here have said that they get months of relief from B2711 by adding solder extensions to the pellet contacts. You might get more by using 3% silver solder, a rare and expensive solder used for electronics in soldering to silver-plated porcelain, but which is quite hard when cool, unlike conventional solders. I buy a new key and get years of relief. A dealer will want to sell you an ignition switch *and* a key because that's the only way that they can give this job a Goodwrench warranty, but its a bulletproof way of solving the B2711 problem for many years.

Once the B2711 is fixed, you can see if the B2750 goes to HISTORY. If it does, clear it and see if it comes back. If it doesn't, then you are done.

[BodybyFisher]

Here is another option to by pass the system by wiring in the proper value resistor

http://vats.likeabigdog.com/

[alvarado626]

Believe me for the last month i have been searching all over the net for an answer

I went thru that web link and some other ones

In my garage i have like 5 different size of resistors soldering together with a 7500 Ohms

even Tried my second key and used it as a resistor and nothing seems to work

I Really appreciated ur time Thank u

[AndyUK1]

Believe me for the last month i have been searching all over the net for an answer

I went thru that web link and some other ones

In my garage i have like 5 different size of resistors soldering together with a 7500 Ohms

even Tried my second key and used it as a resistor and nothing seems to work

I Really appreciated ur time Thank u

There is a guy on allexperts.com who is an expert on cadillacs and has answered many questions on vat key problems and seems very knowledgeable on them.

The site is.... en.allexperts.com/q/Cadillac-Repair-806/ and his name is Rob Painter (sorry I couldn't put the link so you can just click on it,don't know how to do that!!).

Hope nobody on here takes offence at me recommending a cadillac expert from a different site and hope he can help and give you some new advice.

Good luck

[Göran W]

Have You changed the ignitionlock including(!) the orange wireing. The thin cables inside are often damaged from steeringwheel movements.

[BodybyFisher]

Your original intent was to change the turn signal switch

Prior to changing your turn signal switch, your car started, correct?

Changing your turn signal switch required that you remove the steering wheel?, correct?

So you changed your turn signal switch and THEN you could not start, correct?

If I were YOU, I would have removed my steering wheel and checked to see what I did wrong in replacing the TURN SIGNAL switch that would cause this problem.

For instance, did I leave a ground wire off? Did I accidently pull a wire out of the switch?

What in the world would make you CHANGE the ignition switch when it worked BEFORE you did the TURN SIGNAL switch? What would make you THEN play with the resistors to by pass the system when it worked BEFORE messing with the TURN SIGNAL switch.

I don't think that anyone here can help, and you will be lucky if the dealer can help, you must have done something wrong when you did the TURN SIGNAL switch that caused this problem is all I can say.

If I were you, I would put everything back the way it was, including your original ignition switch and I would look at the turn signal switch area to see what I did wrong that would have caused this mess.

Keep in mind that BEFORE you did the turn signal switch NOTHING was WRONG, so changing the ignition switch, by passing with resistors etc, was not the cause and unnecessary.

[BodybyFisher]

I dont know if it was asked, but do you have ANY other codes?

Just for the record, did you do any what I would call crazy diagnostics when you changed the ignition switch? Putting in jumper, back feeding or testing circuits that could have zapped the PCM? On these diagrams you will notice warnings for sensitive circuits.

I have provided the following for reference and for background. You are going to need to do some testing. You should go to the other thread that I referred you to, and do some testing based on what was said in that thread.

DTC P1633 Ignition 0 Switch Circuit

Circuit Description

The PCM is powered with 5 power feeds. Two of these feeds are from the battery, the other three are from the ignition switch and are called Ignition 1, Ignition Supplement and Ignition 0. Ignition 1 and Ignition Supplement are powered any time the key is in the CRANK , RUN or ACC positions. Ignition 0 is powered in ALL key positions except LOCK and CRANK. This diagnostic test is used to monitor the Ignition Supplement voltage received at PCM connector C2 terminal 37. The PCM monitors this voltage and if it drops too low for 1 second, DTC P1633 will set.

Conditions for Running the DTC

• Engine running
• Ignition 1 voltage, PCM connector C1 terminal 19, at least 5.5 volts.

Conditions for Setting the DTC

Ignition Supplement voltage, PCM connector C2 terminal 37, voltage low for 1 second.

Action Taken When the DTC Sets

• The Malfunction Indicator Lamp (MIL) will not illuminate.
• The PCM will command a message to be displayed.
• The PCM may record operating conditions at the time the diagnostic fails. This information will be stored in the Failure Records.

Conditions for Clearing the Message/DTC

• The PCM will turn the message OFF after one run and pass of the diagnostic test.
• A History DTC will clear after forty consecutive warm-up cycles with no failures of any non-emission related diagnostic test.
• A Last Test Failed (current) DTC will clear when the diagnostic runs and does not fail.
• Use a scan tool to clear DTCs.
• Interrupting PCM battery voltage may or may not clear DTCs. This practice is not recommended. Refer to Clearing Diagnostic Trouble Codes in PCM Description and Operation.

Diagnostic Aids

If this DTC is intermittent check terminal contact at the PCM and the condition of the CKT 639 splice for an intermittent open condition

[BodybyFisher]

For reference purposes

DTC P1634 Ignition 1 Switch Circuit

The PCM is powered with 5 power feeds. Two of these feeds are from the battery, the other three are from the ignition switch and are called Ignition 1, Ignition Supplement and Ignition 0. Ignition 1 and Ignition Supplement are powered any time the key is in the CRANK , RUN or ACC positions. Ignition 0 is powered in ALL key positions except LOCK and CRANK. This diagnostic test is used to monitor the voltages received by the PCM at connector C1 terminals 18 and 19. When the engine is running, the PCM will compare the Ignition 1 voltage it receives at connector C1 terminal 19 to the Ignition 0 voltage it receives at connector C1 terminal 18. If the Ignition 1 and Ignition 0 voltages are more than 2 volts different for 5 seconds, DTC P1634 will set.

Conditions for Running the DTC

Engine running

Conditions for Setting the DTC

Voltage difference between Ignition 1 (PCM C1-19) and Ignition 0 (PCM C1-18) inputs greater than 2 volts for 5 seconds.

Action Taken When the DTC Sets

• The PCM will illuminate the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
• The PCM will record operating conditions at the time the diagnostic fails. This information will be stored in the Freeze Frame and Failure Records.

Conditions for Clearing the MIL/DTC

• The PCM will turn the MIL OFF after three consecutive drive trips that the diagnostic runs and does not fail.
• A Last Test Failed (current) DTC will clear when the diagnostic runs and does not fail.
• A History DTC will clear after forty consecutive warm-up cycles with no failures of any emission related diagnostic test.
• Use a scan tool to clear DTCs.
• Interrupting PCM battery voltage may or may not clear DTCs. This practice is not recommended. Refer to Clearing Diagnostic Trouble Codes in PCM Description and Operation.

Diagnostic Aids

If this DTC is intermittent check terminal contact at the PCM and the condition of the CKT 639 splice for an intermittent open condition.

A short to unswitched battery voltage on the Ignition 1 / Ignition Supplement circuit will set this DTC. Symptoms associated with this condition include the inability to shut the engine OFF using the ignition switch.

If the Ignition 0 to the PCM is lost the vehicle will still run but some outputs may not function, if the Ignition 1 voltage is lost or goes below 5.5 volts the vehicle will not run but DTC P1634 should set

[BodybyFisher]

You will notice a triangular warning on the above 2 circuits, it means the following

Handling ESD Sensitive Parts Notice

Notice

Electrostatic discharge (ESD) can damage many solid-state electrical components. ESD susceptible components may or may not be labeled with the ESD symbol. Handle all electrical components carefully. Use the following precautions in order to avoid ESD damage:

• Touch a metal ground point in order to remove your body's static charge before servicing any electronic component; especially after sliding across the vehicle seat.
• Do not touch exposed terminals. Terminals may connect to circuits susceptible the ESD damage.
• Do not allow tools to contact exposed terminals when servicing connectors.
• Do not remove components from their protective packaging until required to do so.
• Avoid the following actions unless required by the diagnostic procedure:
  • Jumpering or grounding of the components or connectors.
  • Connecting test equipment probes to components or connectors. Connect the ground lead first when using test probes.

  [*]Ground the protective packaging of any component before opening. Do not rest solid-state components on metal workbenches, or on top of TVs, radios, or other electrical devices.

[alvarado626]

The reason I fixed the turning signal switch was because the turning signal handle wasn't going back to the original place. Once I changed that, I took it for a test drive and sometimes when I would turn, the horn would honk on its own, so I figured I did something wrong and went back to take steering wheel back of and check what I did wrong but i couldn't find anything wrong. That same day when I put everything back together and tried to start the car it wouldn't start. That's when i found out about code # b2750 and b2711 and I did my research on the internet, I took my key to the dealer I was told it was #13 which leads me to a 7500 ohms thats when i started to build my own resistor bypass and tried about 4-5 different ways . I connected the resistor to two white wires towards the base and noting happened. Looking through the internet i read an article where it said it could be the ignition switch or key pellet yet the car is still the same.

Since the turn signal handle was broken from the housing i went to the junkyard and bought a turn signal switch, a wiper switch with the housing, I replaced everything with the new switches and it still doesn't turn on. As of today I have removed the dashboard top, removed the cluster and I'm getting a reading of 7500 ohms.

THANK U FISHER

[Cadillac Jim]

If you have a resistor soldered in the wiring harness but do not disconnect the terminals that hook to the lock, then, when the key is in, you have *both* resistors in the circuit. So, with that setup, you have 750 Ohms, not 1500 Ohms, when you try to start the car.

If you disconnected the key circuit when you put the 1500 Ohm resistor in the wiring harness, then you should be OK.