Wierd Electrical Gremlin on SL320 (99/UK)

I drive a '99 SL320 (UK/R.H.Drive) and have recently been plagued with a strange electrical gremlin.

On starting, although the motor runs normally, the car occasionally "loses" various ancillary electrical functions (namely: wipers, screen wash, radio, mirror adjust, headlight flash, seat heat..). More worryingly, it also develops a fault in the indicators where a right-turn on the "stalk" results in the left-side indicators flashing.

Brake lights, reverse lights, side and headlight, and hazard (4 way) flashers are not affected.

I have tried a restart and an alarm system reset to no avail. Usually, after about ten minutes of (very careful) driving with hand-signals only, the system recovers and everything functions normally.

Of course, this fault will not manifest itself when the vehicle is taken to the dealership!

Any ideas would be gratefully received.

Thanks in advance

Oggip

It sounds to me like you might have a faulty regulator in the generator. If the car looses its charge from the generator it will drop all equipment not regarded essential for driving the car (so that you can go as long as possible on the battery).

You can pretty easily check this one out your self. Connect a voltmeter to the battery (there is a battery terminal under a small black plastic-cover in the engine compartment marked with a +) and check the charge-voltage when everything is working fine. You should read about 14V. Now, repeat this the next time you experience the fault, you should now measure less than you did when everything was ok (probably 12-12.5V). If this happen, its a clear indication that the generator (or just the regulator) needs to be replaced.

Best regards,

Thomas.