Hello All,
I have a problem with my 2007 CLS63. She now has 111,200K miles. I need some help. I love this car and it is too nice to throw away. I don't want to do any LS1 or other radical swap out either. I just want what is there to work.
I know that any replacement ECU as well as key fobs and ignition components need to be programed to the specific VIN. I need to know if the front Signal Acquisition Module or SAM / Fuse and Relay panel require the same treatment to work. Programed plug and play replacement ECU from $700.00 to $1500.00. Front SAM Fuse / Relay panel $200.00 to $500.00. SAM programing if required is unknown. Probably a minimum of 2hrs shop time with Star System. I don't want to replace the ECU if it is the SAM due to cost.
The problem is it has an intermittent no start condition (i.e. starter won't crank the engine over to start it). I have looked through many threads and replies here and on other online resources. I have a copy of the WIS/ASRA and can read schematics / wiring diagrams.
The symptom, when it occurs, is when using the Keyless Go button or turning the Fob / key in the ignition switch. The battery is not the culprit. I have replaced the starter relay, fob batteries, starter, battery, brake pedal switch so far. Being intermittent it has been very hard to track it down.
This has been going on for around 6 - 8 months. I love this car, it is such a fun car to drive but I'm getting very tired of this problem. Taking a car with an intermittent electrical problem to the dealer is a complete waste of 2 hrs of shop labor time and charges minimum. Don't ask how I know this.
My reading of the internet, wiring diagrams and basic testing indicates the possibility of a faulty ECU internal circuit or the Front SAM fuse / relay panel control unit internal circuit.
Conditions and Symptoms in fail mode;
Can happen when cold first start or after being driven any normal distance short or long. Also if the security system is activated / deactivated or not between starts with the fob or handle buttons.
The steering wheel never remains locked and repeated hitting of the steering wheel have no effect on the no crank condition. Was told to try this to eliminate the steering lock unit.
With Keyless Go fob inside car, foot on brake, hit the start / stop button, dash lights and all accessory items activate but no starter action or noise sometimes, sometimes a very fast engagement of the starter for less than a full revolution of engine, then disengage and nothing on that button push most times.
With Keyless Go fob in ignition switch, foot on brake, turning the switch to start, Exactly the same as above.
With repeated cycling of the ignition with either the switch or start / stop button, sometimes it will start as if it never had a problem after 1 or 15 attempts..
Sometimes when exasperated with multiple attempts, with ignition still in run condition, foot still on brake, shaking head in despair, it cranks and starts after a 10 to 30 second delay as if it never had a problem.
In every case, when it won't crank after multiple attempts, I can leave the ignition in the run condition, foot off brake and fob outside the car, remove the starter relay and jump the switched voltage ports to the starter, it cranks and starts every time with ease.
One additional symptom that has started quite recently through this failure time period is that, with the ignition in run or cycling through, the radiator fans can begin running at full speed, slow down and run up to high again, or just remain on high. A/C condition has no effect.
The fans can stay on for about 30 seconds after ignition is off and fob is outside the car. Temp gauge is always at a relatively normal position to engine condition, warm or cold.
The car has always had the occasional, again intermittent, parking assist warning light and alarm come on at less than 5 MPH when nothing is near the car front or rear. At the front in Drive or rear in Reverse, mostly noticed in Drive, that has been intermittent throughout the cars life with me from 75K miles. Don't think these are related but hell, I'm not sure.
Thanks in Advance for any insight that anyone can provide.