[hugh wilson]

Wife hit a snow bank and did minimal front end damage to the car. Car now says that "limited to 55 mph" I check error codes and came up with a ton. abs 1227,1298;ddm b1328,u1713;IPC u1040,u1000;IRC u1016;PCM p1571,p1644,u1040;RIM b1328;RSS c0577.c0579;RSS c0640,c0710;TTN u1016;Vtd b3055
Talked to the dealer and he said they would replace the PCM and if that doesn't work then replace the EBCM, and if they don't work I still have to pay for them. That is almost as much here in Canada as the car is worth, don't know what to do.
Also when the car starts often ABS,Airbag,Traction Control lights come on, not always, and not always do they stay on. If they do heated seats, heater will not work. Any input would be appreciated!

 

[N*Caddy]

C1227 - Left Rear Excessive Wheel Speed Variation
C1298 - PCM Class 2 Serial Data Link Malfunction
P1571 - Traction Control Torque Request Circuit
P1644 - Traction Control Delivered Torque Output Circuit
C0640 - Right Front Normal Force Circuit Malfunction
C0577 - Left Front Solenoid Circuit Low
C0579 - Left Front Solenoid Circuit Open
C0710 - Steering Position Signal Malfunction
These are the codes you should focus on. Unfortunately I discovered that MOST GM dealer in GTA are incompetent in regards with Cadillac (and I am talking about the one labeled "specialists"). Looks like most of the time they spend their time under a Cavalier hood.
So back to the codes:
PCM is the LAST module I would start with. Your main focus is the EBTCM.
Hopefully that is not it, is just the connector to the EBTCM. However, the C1227 indicates you may need a new left rear wheel hub. The next 4 codes indicate the EBTCM (PCM and CVRSS module can't get a reply from EBTCM) Again start with checking the connector. Have you done any recent engine work (like TC/WP area) involving coolant spill?
C0577 and C0579 indicates that you need to replace your left front strut ($$$$$$$!!!!!).
C0710 indicates a issue with the steering position sensor, a very common issue with the '98+ Seville.
These are the most important codes you should focus on, the other ones are to be dealt it once you have these sorted out. Definitely are expensive repairs, specially in Canada.
Most of the EBTCM and CVRSS related codes will trigger the "Speed limited to ..." message. Basically in this moment your ABS/TC and Stability systems are disabled (kind of like driving a Toyota Corolla).
First you make sure the EBTCM connector is snug and clean (so no contact issues) and the harness to the wheel hub and strut is intact. After that wheel hub >$200 (here in Canada), strut ~$1000 (here in Canada, maybe ~800+shipping+fees from US). EBTCM control module ~$600 in Canada (half that + fees + shipping in US). If you don't do the work yourself, double the price.

 

[hugh wilson]

I did replace the front struts 1/2 yr ago.....got some gas ones from arnott industries in Florida. They have the resisters that plug in so the computer thinks you are still using electric control struts. Can the PCM from another 2001 be used in my car, wrecker here has one, sold me a back strut for $100 and will let the pcm go for $125, just don't know if it can be reflashed. The dealer he said that a new one is $1100 plus $125 flashed for the car. That is why if it doesn't work then I have to keep it! Thanks for your reply

 

[N*Caddy]

Sir, FORGET ABOUT THE PCM, 99% is NOT IT. Since you have aftermarket strut(s) on your car the all bets are off (is not the first aftermarket part to go wrong by no means). You have EBTCM, PCM and CVRSS codes, you have codes between EBTCM and PCM, you have codes between CVRSS and EBTCM. Notice how EBTCM is in involved in any combination?
As I mentioned the order is:
1. Check EBTCM connector
2. Check the harness between EBTCM and RHS Rear wheel hub (especially the connector in the back of the hub). If nothing wrong with it then change the wheel hub.
3. Check the harness between CVRSS module and left front strut. Check that bypass resistor (what you got in there is a cheap patch not a quality active strut). The only way to restore the suspension back to active setup is using OEM struts. You can add a 4.7KOhm resistor in there and keep the aftermarket strut (if you don't care about the ride).
4. If 1 test good, 2 and 3 are fixed and still issues (like C0640, P1644, P1571) then replace EBTCM (only the controller part NOT the whole assembly).
5. Change the steering wheel position sensor if the C0710 is still on after EBTCM replacement.
PCM controls engine and transmission, you can still drive the car so most likely is FINE, none of the codes pinpoint straight to the PCM. Talk with that person about the EBTCM not the PCM (should be around $50-$75 - no programming required).