: 04 ext Shuts off randomly.



Bigrick31
07-01-13, 05:58 PM
About 2 weeks ago while driving my ext the traction control light came on saying service stability system and the the truck would go into reduced power mode. I did a lot of research on the subject and it seemed that the most likely cause was either a bad throttle position sensor or a bad pedal position sensor. Before replacing either sensor I carefully inspected the wiring coming off of the Tps. Everything looked good and I ended up replacing both the APS and the entire throttle body. During the process my battery had died I had tested the battery before I changed the other parts and I was reading 12v with the truck off and 14v with the truck running with High beams on and AC on full blast. After the battery dropped below 9v (an optima yellow top) I attempted to recharge the battery but the voltage refused to increase.

I purchased a new battery and the truck drove fine for a couple of days. Then one day while driving every time I would hit a bump in the road my doors would unlock and then lock again plus the gas pedal wouldn't respond for maybe 5 seconds and then everything would work again. Finally I hit a bump and the truck shut off completely. The navigation and dash lights all worked but the engine was off and pulling over to the shoulder the truck wouldn't start any more the engine wouldn't even crank nothing happened at all when I i turned the key but the electronics would come on.

I got the truck towed home and noticed that one of the bulbs in each headlight were on and would nit turn off. I think it's a blinker bulb the top left bulb if your looking at the driver side headlight head on and the same one on the passenger side but that one is top right. So I disconnected the battery.

I havnt been able to pull any codes from the truck because every time I try my scanner says unable to communicate with vehicle. I was previously able to to get my scanner to communicate with the vehicle which is when I changed the TPS sensor but after the truck continued to go into reduced power mode I tried using my scanner again but it wouldnt work that is when I changed the TB and Battery. I made sure to check my cigarette lighter fuse as its the same fuse used to power the obd2 system and it was good. While talking with a friend he suggested I may have a bad ECM I checked online and found I could get a working used ECM flashed to my vin for $100 I'm going to give that a shot when u get home.

I was wondering if anyone had any ideas what the problem may be just in case it isn't my Ecm. I've also tested all of the relays in the fuse box under the hood and even tested my ground wires at the frame and engine block which all test as good.

Bigrick31
07-01-13, 08:07 PM
UPDATE... Replaced ECM and nothing changed. My scanner is still unable to communicate with the vehicle I hear nothing when I turn the key to start the truck. The security light (picture of a car with a lock on the dash) is stuck on and the I still have the one bulb in each headlight on non of which will turn off unless I disconnect the battery.

the cadillac man
07-01-13, 08:53 PM
UPDATE... Replaced ECM and nothing changed. My scanner is still unable to communicate with the vehicle I hear nothing when I turn the key to start the truck. The security light (picture of a car with a lock on the dash) is stuck on and the I still have the one bulb in each headlight on non of which will turn off unless I disconnect the battery.

I wonder if it is the bcm going bad(it works the lights and security system)

Bigrick31
07-01-13, 09:16 PM
is there any way to test the BCM before going to the dealer for a new one? Do you think theres any chance its the ignition switch or the passlock system?

the cadillac man
07-01-13, 11:45 PM
is there any way to test the BCM before going to the dealer for a new one? Do you think theres any chance its the ignition switch or the passlock system?

Well is anything else in the truck acting up (the bcm works everything in the truck
Lights(interior and exterior)
Locks
Both front door modules(door switches)
Wipers(front and rear)
Radio and amp(including the cd changer 03+)
Gauges
Seats(both memory and seat controls via seat module)
Locks
Keyless entry
Onstar system
Rear seat entertainment system
Pass lock system/anti theft system
And recives data and sends data from and to the PCM via the class-2 data bus

If multiple things in the list is acting up then most likely the bcm is the cuplrit

Bigrick31
07-02-13, 09:07 AM
Everything works as it should in the vehicle the only time then door locks or headlights give me trouble is randomly when I hit a bump in the road which will cause the truck to either shut off completely or go through a 5 second reset. Ocasionally when I hit a bump I will get the traction control disabled message but the truck no longer goes into reduced power mode. That is when the truck actually runs. Oh and the keyless entry dosnt work when the truck won't start. When the truck starts and runs normally the keyless entry works.

the cadillac man
07-02-13, 12:10 PM
Everything works as it should in the vehicle the only time then door locks or headlights give me trouble is randomly when I hit a bump in the road which will cause the truck to either shut off completely or go through a 5 second reset. Ocasionally when I hit a bump I will get the traction control disabled message but the truck no longer goes into reduced power mode. That is when the truck actually runs. Oh and the keyless entry dosnt work when the truck won't start. When the truck starts and runs normally the keyless entry works.

I would be checking ground connections as it sounds like one is loose
It may be tied into the traction control message not sure but most likely its because of low voltage(loose connections can cause this)

First clean both battery cables and terminals to see its a bad connection at the battery(do this first)

Bigrick31
07-07-13, 12:43 PM
Ok I cleaned the battery terminals really well and I still get nothing. I checked continuity between the battery negative and the ground wires that go to my frame and engine block both test good. I did notice when I tried to start the truck after cleaning the battery terminals that I cold hear what sounds like the fuel pump making a pfft sound after every failed start. Just to clarify the truck will not crank but all electronics work just fine. Again after attempting to start the truck I had to disconnect the battery because there was a bulb in each headlight that remained on.

Edit- Dont know if this matters but my fuel gauge reads empty however when the truck last ran I had close to a full tank of gas.

the cadillac man
07-07-13, 01:01 PM
Ok I cleaned the battery terminals really well and I still get nothing. I checked continuity between the battery negative and the ground wires that go to my frame and engine block both test good. I did notice when I tried to start the truck after cleaning the battery terminals that I cold hear what sounds like the fuel pump making a pfft sound after every failed start. Just to clarify the truck will not crank but all electronics work just fine. Again after attempting to start the truck I had to disconnect the battery because there was a bulb in each headlight that remained on.

Edit- Dont know if this matters but my fuel gauge reads empty however when the truck last ran I had close to a full tank of gas.

Sounds like a module

Bigrick31
07-07-13, 01:06 PM
I can find used BCMs on ebay for about $30 then I guess I just need to tow the truck to the dealer to have it programmed or can i just bring the module to the dealer and then install after programming or is a used BCM a bad idea?

the cadillac man
07-07-13, 01:14 PM
I can find used BCMs on ebay for about $30 then I guess I just need to tow the truck to the dealer to have it programmed or can i just bring the module to the dealer and then install after programming or is a used BCM a bad idea?

I don't know I haven't had to it so far but I recommend the programming be left to the dealer(I went through this kind of issue with my PCM except it kept my truck from starting)

Bigrick31
07-07-13, 01:26 PM
Ok bought the BCM will report back when it arrives.

the cadillac man
07-07-13, 04:11 PM
Ok bought the BCM will report back when it arrives.

I feel your pain I had a car that had bcm issues and it would do all kinda of crazy crap(one time I couldn't get the engine to start it would crank but not run)

Bigrick31
07-10-13, 05:59 PM
Got the new BCM in just now called the Cadillac dealer near me and they said I had to have the new BCM installed in the vehicle for them to reprogram it. Im going to install the new BCM and have my truck towed over to the dealer. If this dosnt work they are going to run a diagnostic for me to see whats wrong.

Bigrick31
07-10-13, 08:23 PM
So its $150 for the dealer to reprogram the BCM it would have been $300 but I Already installed the BCM prior to having the vehicle towed to the dealer. They will call me tomorrow to let me know if that worked. If not its $450 for an extensive diagnostic.

the cadillac man
07-10-13, 10:37 PM
So its $150 for the dealer to reprogram the BCM it would have been $300 but I Already installed the BCM prior to having the vehicle towed to the dealer. They will call me tomorrow to let me know if that worked. If not its $450 for an extensive diagnostic.

Its around the same ball park on price I paid to have the pcm replaced in my truck

Bigrick31
07-11-13, 07:56 PM
Well it wasnt the BCM they reprogrammed it and the truck still wont start. They are going to call me back tomorrow when they figure out whats wrong.

the cadillac man
07-11-13, 09:27 PM
Well it wasnt the BCM they reprogrammed it and the truck still wont start. They are going to call me back tomorrow when they figure out whats wrong.

The only other module that can cause this is the PCM

Bigrick31
07-12-13, 04:11 PM
Just got the truck back from the dealer. They said after they reprogrammed the BCM the truck would crank but wouldnt start. They ended up finding a bad ground wire behind the engine. They said it looked good visually but the wires under the insulation broke apart. With reprogramming the BCM and finding and fixing the bad ground it only cost me $445 which is a huge relief.

the cadillac man
07-12-13, 05:14 PM
Just got the truck back from the dealer. They said after they reprogrammed the BCM the truck would crank but wouldnt start. They ended up finding a bad ground wire behind the engine. They said it looked good visually but the wires under the insulation broke apart. With reprogramming the BCM and finding and fixing the bad ground it only cost me $445 which is a huge relief.

Glad to hear you got it fixed(just wish you didn't have to spend the money on the bcm before you found the bad ground cable)

Bigrick31
07-12-13, 05:36 PM
At least now I have a spare ECM and BCM that are programed to my vehicle should I have problems in the future lol. Thanks for all your help cadillac man

the cadillac man
07-12-13, 09:46 PM
At least now I have a spare ECM and BCM that are programed to my vehicle should I have problems in the future lol. Thanks for all your help cadillac man

That's a good thing to have spare parts

The engine computer is called a powertrain control module as it works both the engine and transmission

Glad to help

Bigrick31
07-23-13, 06:56 PM
Turns out my troubles are not over yet. The truck drove fine for about a week after the dealer fixed it. There were some minor issues like a rough idle or my projected fuel economy being a lot lower than usual but I figured the truck just had to re learn a few things since a lot had been changed. However I was going to go for a bit of a drive this past weekend and right when I pulled out of my driveway I get hit with the "service stability system" message and reduced engine power message. I got a tow truck on its way right now to pick the truck up and take it to the dealer. The only issue is if I try to drive the truck right now it drives fine hopefully the dealer can replicate the problem.

the cadillac man
07-23-13, 07:09 PM
Turns out my troubles are not over yet. The truck drove fine for about a week after the dealer fixed it. There were some minor issues like a rough idle or my projected fuel economy being a lot lower than usual but I figured the truck just had to re learn a few things since a lot had been changed. However I was going to go for a bit of a drive this past weekend and right when I pulled out of my driveway I get hit with the "service stability system" message and reduced engine power message. I got a tow truck on its way right now to pick the truck up and take it to the dealer. The only issue is if I try to drive the truck right now it drives fine hopefully the dealer can replicate the problem.

Given the messages it may be the PCM as the stability system is tied into the PCM

I know how you feel about it I was in your shoes but my truck wouldn't even start or crank(the data bus for the throttle went down and the PCM shut the engine down) and I was lucky it did or i would have plowed through a Walmart as when I got it home via tow truck and got a code scanner I found out the tps was showing I had the pedal to the floor(not good)

You did the right call by not taking the risk and driving it when it showed the message

Mine would lag on the throttle before the PCM died

Bigrick31
07-23-13, 07:36 PM
Given the messages it may be the PCM as the stability system is tied into the PCM

I know how you feel about it I was in your shoes but my truck wouldn't even start or crank(the data bus for the throttle went down and the PCM shut the engine down) and I was lucky it did or i would have plowed through a Walmart as when I got it home via tow truck and got a code scanner I found out the tps was showing I had the pedal to the floor(not good)

You did the right call by not taking the risk and driving it when it showed the message

Mine would lag on the throttle before the PCM died

Your story with the TPS sounds scary it makes me wish we had the old cable style system.

as for the PCM I just replaced it a couple of weeks ago with a tested good working unit. I did this when I first started getting the service stability message I first changed out the Accelerator position sensor then the entire throttle body then the PCM and finally I replaced the BCM. If it is the PCM then my original PCM and the PCM I purchased online would have to have the same problem which seems unlikely or am I missing something here? Also I only get the message when I hit a bump or in this case when I drive the truck in and out of my driveway I actually drive off of the curb as my driveway is wider than the slanted part that merges into the street.

What happened this weekends was I backed out of the driveway firs the rear tires drop off of the curb and then the front ones. Then when I am far enough back I put the truck into drive and thats when I got the error messages. However I just did this exact same thing right now to drive the truck up onto a tow truck and the truck worked just fine.

the cadillac man
07-23-13, 10:16 PM
Your story with the TPS sounds scary it makes me wish we had the old cable style system.

as for the PCM I just replaced it a couple of weeks ago with a tested good working unit. I did this when I first started getting the service stability message I first changed out the Accelerator position sensor then the entire throttle body then the PCM and finally I replaced the BCM. If it is the PCM then my original PCM and the PCM I purchased online would have to have the same problem which seems unlikely or am I missing something here? Also I only get the message when I hit a bump or in this case when I drive the truck in and out of my driveway I actually drive off of the curb as my driveway is wider than the slanted part that merges into the street.

What happened this weekends was I backed out of the driveway firs the rear tires drop off of the curb and then the front ones. Then when I am far enough back I put the truck into drive and thats when I got the error messages. However I just did this exact same thing right now to drive the truck up onto a tow truck and the truck worked just fine.

No worries on that as the PCM shut the engine off right after it went into reduced power mode(I am thankful it did as I wasn't the only one in the truck) plus it would be a bad image on us caddie owners had it barreled into Walmart that day(remember the runaway Toyotas) I doubt I would have survived that day but never know and I don't think I would have wanted to find out

If I did have that happen and I survived my truck would have been totaled most likely due to the impact with the building

I am wondering if a wheel sensor is bad or a wire is loose/chaffed though given how the message is at random

I have only seen that message one time and that was when I had overworked my brakes(was on a trip so I didn't get to check for codes and the issue went away after I restarted the truck)

Bigrick31
07-24-13, 05:56 PM
I actually don't know if my wheel sensors are still working. I purchased a set of 18s from someone who had just purchase a 2010 escalade and wanted aftermarket wheels. I never got around to getting the the new wheels set up to my wheel sensors. The dealership just called and asked me if I had already replaced my AP sensor or if I had replaced the ignition switch. I told them I changed the APS but not the ignition so that's where they think the problem is coming from at the moment.

the cadillac man
07-24-13, 05:59 PM
I actually don't know if my wheel sensors are still working. I phrased a set of 18s from someone who had just purchase a 2010 escalade and wanted aftermarket wheels. I never got around to getting the the new wheels set up to my wheel sensors. The dealership just called and asked me if I had already replaced my AP sensor or if I had replaced the ignition switch. I told them I changed the APS but not the ignition so that's where they think the problem is coming from at the moment.

I would want to be sure I ain't liable for parts cost if they are going to just throw parts at it unless it does fix the problem

Mark Edward Morrison
07-25-13, 07:48 PM
That's a great point Cadillac man! Who could only guess what your bill might be! I am SO glad I have a buddy that's a a Cadillac Mechanic and does my work on the side at the Cadillac dealer he works at! You talk about saving some money, he has saved me a TON in repairs over the years!

the cadillac man
07-25-13, 10:57 PM
That's a great point Cadillac man! Who could only guess what your bill might be! I am SO glad I have a buddy that's a a Cadillac Mechanic and does my work on the side at the Cadillac dealer he works at! You talk about saving some money, he has saved me a TON in repairs over the years!

Good to hear you have someone who is a Cadillac mechanic to work on your truck I am the same way as I only trust my local dealer with my truck or my parents trucks(my dad has a hummer h2 my mom has a 02 escalade)
Any work I can't do myself I get the dealer to do it

Bigrick31
07-29-13, 09:21 AM
Well the dealer I'm dealing with is beginning to drive me crazy lol. They had me pick the truck up on Friday they said during their extensive diagnostic they found codes B2961 P1125 and C0455. They said that C0455 means that they need to reprogram the SES module which they did and then they reset the codes but the P1125 code wouldn't reset which they say means the app sensor is bad. I had previously replaced the app sensor which I told the dealer so they just inspected the wiring and said it looked good. So they said the truck was fixed and had me pick it up. When I had the truck towed to them this time they told me they would cover the tow if the problem was related to the last time I brought the truck in but when I went to pick up the truck they charged me $70 for the tow stating it was a different issue. It would seem to me if I bring the vehicle in because of the reduced engine power and service stability message and then a week later after its supposed to have been fixed I bring it in again for those same error messages that it would be considered the same problem. The bill this time came out to $370

Any ways this morning I start the truck up and right away I get the service stability and reduced engine power messages. I'm going to be calling the dealer again later and have them pick the truck up from my house while I'm at work.

Bigrick31
07-29-13, 12:25 PM
Just got off the phone with Cadillac they said the truck will probably give me those error messages about 7-8 more times because the truck is going through the relearning process they said to just shut the truck off for 30 seconds and then it should reset the message and drive fine.

Cadillac Cust Svc
07-29-13, 01:19 PM
Just got off the phone with Cadillac they said the truck will probably give me those error messages about 7-8 more times because the truck is going through the relearning process they said to just shut the truck off for 30 seconds and then it should reset the message and drive fine.

Hello Bigrick31,

I am sorry for any trouble you are experiencing with your Escalade. I see you were able to make contact with the dealer in regards to your issue. If there is anything you would like to further discuss, please reach out to us via private message.

Regards,

Laura M.
Cadillac Customer Care

Bigrick31
08-12-13, 02:23 PM
Well the truck has died on me another 10-15 times now and today it finally got to the point where shutting the truck off for 30 seconds and starting it again wont work. Once I start the truck I immediately get the same error messages as before. looks like the truck is going back to the dealer for round 3.

the cadillac man
08-12-13, 04:32 PM
Well the truck has died on me another 10-15 times now and today it finally got to the point where shutting the truck off for 30 seconds and starting it again wont work. Once I start the truck I immediately get the same error messages as before. looks like the truck is going back to the dealer for round 3.

Try a different PCM

Bigrick31
08-12-13, 06:37 PM
Try a different PCM
I could try putting the old PCM back in well see what happens when the dealer calls back. They just came by to grab the old APPS they said they think the auto parts store gave me the wrong part and that usually the APPS comes with an entire pedal assembly which dosnt really make much sense to me. It seems like a waste of money to buy a new pedal when all you need is the sensor.

the cadillac man
08-12-13, 08:38 PM
I could try putting the old PCM back in well see what happens when the dealer calls back. They just came by to grab the old APPS they said they think the auto parts store gave me the wrong part and that usually the APPS comes with an entire pedal assembly which dosnt really make much sense to me. It seems like a waste of money to buy a new pedal when all you need is the sensor.

I find them saying the pedal and sensor has to be replaced

Bigrick31
08-21-13, 09:36 AM
It turns out the App sensor I bought from the auto parts store was defective. The dealer installed my old Apps and now the truck has been running smoothly all week.

the cadillac man
08-21-13, 11:39 AM
It turns out the App sensor I bought from the auto parts store was defective. The dealer installed my old Apps and now the truck has been running smoothly all week.

That's great to hear