Lots of TCS/Drive By Wire codes.
10-19-2008, 05:42 PM
#1
Instructor
Thread Starter
Lots of TCS/Drive By Wire codes.
Here's the deal. I have been dealing with this problem about 4 years now but am going insane as I never know when it's going to happen. Sometimes I drive it for weeks with no problems. Other times it will do it all day.
I am driving along and get the "service TCS warning" and lose all but about 2 horsepower to the engine. Those who have experienced this knows it can be quite dangerous as the car barely has enough umph to get off the road safely. Usually turning the car off for a few seconds will get the car back normal. As stated above sometimes I can drive it for hundreds of miles before it happens again. But yesterday it simply wouldn't fix itself. I limped it home and today it is still being finicky. Here are the codes I get when it happens:
P1125 Accelerator Pedal Position (APP) System
P1286 Accelerator Pedal Position (APP) Sensor 3 Performance
C1241 Magnasteer Malfunction
C1278 TCS Temporarily Inhibited By PCM
U1064 Lost Communications with BCM
Note that I can clear out the codes and they all are gone until the car goes nuts later down the line...that's when they all reappear.
Backstory: The care was involved in a wreck the first month I had the car (5 years ago). The wiring was damaged around the computer but it was repaired with a new harness (though the dealership is a joke so who knows if they actually replaced it). Several months go by with no issues...may have even been a year. Then the problem above occurs. The dealer looks at it and says it's the computer so I have them replace it. All is fine for another 6 months or so. Then the problem starts happening again. After reading about similar issues with the gas pedal on Pontiac GTOs I replace the pedal with a new one. Issue is still there. I get to looking at the harness next to the battery and none of them were put back properly. They are just jammed down in the fender when they are all supposed to be clipped on the wall.
In my opinion I feel it is a loose connection due to the job not being fixed properly the first time. With the connectors in the fender not being secured a wire could be working loose somewhere causing it to cause all these codes at once. Does this sound right? Or could it be just a bad ground (since I have read so much about grounds causing so many issues)? I have checked all the ground I could find under the hood and they all look good but I cleaned them just to be safe. And it does have a new battery too.
I guess really I am just writing this to see if there is something specific I should look for. I am planning on pulling the fender off to see if there is any corrosion or loose connections but want to know if anyone has seen the same group of codes all appear at once and can give some suggestion to the issue.
Thanks in advance.
I am driving along and get the "service TCS warning" and lose all but about 2 horsepower to the engine. Those who have experienced this knows it can be quite dangerous as the car barely has enough umph to get off the road safely. Usually turning the car off for a few seconds will get the car back normal. As stated above sometimes I can drive it for hundreds of miles before it happens again. But yesterday it simply wouldn't fix itself. I limped it home and today it is still being finicky. Here are the codes I get when it happens:
P1125 Accelerator Pedal Position (APP) System
P1286 Accelerator Pedal Position (APP) Sensor 3 Performance
C1241 Magnasteer Malfunction
C1278 TCS Temporarily Inhibited By PCM
U1064 Lost Communications with BCM
Note that I can clear out the codes and they all are gone until the car goes nuts later down the line...that's when they all reappear.
Backstory: The care was involved in a wreck the first month I had the car (5 years ago). The wiring was damaged around the computer but it was repaired with a new harness (though the dealership is a joke so who knows if they actually replaced it). Several months go by with no issues...may have even been a year. Then the problem above occurs. The dealer looks at it and says it's the computer so I have them replace it. All is fine for another 6 months or so. Then the problem starts happening again. After reading about similar issues with the gas pedal on Pontiac GTOs I replace the pedal with a new one. Issue is still there. I get to looking at the harness next to the battery and none of them were put back properly. They are just jammed down in the fender when they are all supposed to be clipped on the wall.
In my opinion I feel it is a loose connection due to the job not being fixed properly the first time. With the connectors in the fender not being secured a wire could be working loose somewhere causing it to cause all these codes at once. Does this sound right? Or could it be just a bad ground (since I have read so much about grounds causing so many issues)? I have checked all the ground I could find under the hood and they all look good but I cleaned them just to be safe. And it does have a new battery too.
I guess really I am just writing this to see if there is something specific I should look for. I am planning on pulling the fender off to see if there is any corrosion or loose connections but want to know if anyone has seen the same group of codes all appear at once and can give some suggestion to the issue.
Thanks in advance.
10-19-2008, 11:52 PM
#2
Tech Contributor
Member Since: Dec 1999
Location: Anthony TX
Posts: 32,736
Received 2,180 Likes
on
1,583 Posts
CI 6,7,8,9,11 Vet
St. Jude Donor '08
The Throttle By Wire system does not have any ground wires persay. It is a descrete system that deals with the Throttle Actuation Control (TAC) module, Throttle Peddle switch, Throttle Body position switch and PCM. There wired together in their own circuit. If the connections between any of those are compromises, the PCM will put the car into REDUCED POWER MODE and yea,,,it sucks!!
If I were you, I would start where you know theres an issue. The wiring at the PCM and TAC Module is a good start. They have to be 100%. and yes, mounted properly.
Start by checking continuity between the P1125 Accelerator Pedal Position Sensor & P1286 Accelerator Pedal Position (APP) Sensor 3 Performance wires. Is the acellerator switch properly connected??
BC
If I were you, I would start where you know theres an issue. The wiring at the PCM and TAC Module is a good start. They have to be 100%. and yes, mounted properly.
Start by checking continuity between the P1125 Accelerator Pedal Position Sensor & P1286 Accelerator Pedal Position (APP) Sensor 3 Performance wires. Is the acellerator switch properly connected??
BC
