a32amg

Hello dear friends:

I encountered a very weird problem. If I use my key fob to start the car (or turn to position 2), some items won’t work until like 15 minutes later. On the other hand, if I use keyless to start the car, everything works fine.

Symptom:

1. Use key fob to turn on the car or switch to position 2, the following things behaves abnormally:

- Head lights don’t automatically turn on. (Headlight control in auto) Needs to manually turn it on by switching to always on.

- Comand doesn’t automatically turn on. Can be manually turned on by pressing power button.

- Cigarette lighter socket doesn’t have power.

- Steering wheel buttons that control gauge cluster don’t work. Volume control does work.

- Seat heating or ventilation function doesn’t work. But adjustments do work.

2. After running for 1x minutes, above things start to work all together. This time period is for cold start. For subsequent startups the time needed to have these functions come back becomes like 1~2 minutes.

3. If I use keyless button to start up the car, everything is fine. All of above items immediately turn on or function normally.

4. Use DAS to do diagnostics, no fault code is found in EZS, front SAM, rear SAM. The only thing observed is that “Circuit 15R”* is off until above mentioned electronics starts to work. I guess this is something that sends out signal to wake up devices and enable them?

*Note: DAS main menu -> Control unit -> Body -> Electronic Ignition Switch -> Actual values -> Status of terminals



Car info:

- R230 2003 SL350 European spec

- Front and rear battery fully charged

- Key fob battery has been replaced



It seems like some portion of CAN won’t do its job for a while if key fob is used. This problem has persisted for few months already. Please help. Thanks in advance.