Hard to diagnose electronic malfunction
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W203 C200
Hard to diagnose electronic malfunction
Hello All,
I own a 2002 W203 C200 Kompressor with 55k miles on it. The car has not been in use for quite a long time, it was sitting without a battery. Some days ago I decided to start it up, I bought and installed a brand new, high quality 74Ah battery. The car starts, however I'm experiencing some hard to diagnose electronic malfunctions with it.
1. Sometimes I can't start the engine, I turn the key to the ignition position - everything seems to be fine, but when I try to start the motor nothing happens, no single crank. After 7 - 8 tries it usually starts normally.
2. Hazard lights button and "airbag off" indicator stay on all the time - all lights are off, key is not inserted but illumination of the button and indicator never goes off and drains the battery.
3. Some Instrument cluster dash lights work only during the self-test procedure, when the key is at the "ignition" position. For example, I have a broken ABS sensor, I can see "BAS/ESP malfunction" communicate on the instrument cluster screen, but ABS/ESP light is not illuminated. The same with the parking brake, MIL light - I can see communicates on the screen, but no dash lights. Bulbs are OK.
So far I have put a brand new battery, checked the grounds, checked for water or moisture in a fuse boxes (especially in a front one, where the SAM module lives), checked the charging system. Everything seems to be fine. OBD scanner shows only one malfunction code - something with a throttle body sensor. Do you have any ideas what can cause those problems? It might be a broken SAM module, but maybe there is something else that I can check before replacing SAM.
Regards,
MC
I own a 2002 W203 C200 Kompressor with 55k miles on it. The car has not been in use for quite a long time, it was sitting without a battery. Some days ago I decided to start it up, I bought and installed a brand new, high quality 74Ah battery. The car starts, however I'm experiencing some hard to diagnose electronic malfunctions with it.
1. Sometimes I can't start the engine, I turn the key to the ignition position - everything seems to be fine, but when I try to start the motor nothing happens, no single crank. After 7 - 8 tries it usually starts normally.
2. Hazard lights button and "airbag off" indicator stay on all the time - all lights are off, key is not inserted but illumination of the button and indicator never goes off and drains the battery.
3. Some Instrument cluster dash lights work only during the self-test procedure, when the key is at the "ignition" position. For example, I have a broken ABS sensor, I can see "BAS/ESP malfunction" communicate on the instrument cluster screen, but ABS/ESP light is not illuminated. The same with the parking brake, MIL light - I can see communicates on the screen, but no dash lights. Bulbs are OK.
So far I have put a brand new battery, checked the grounds, checked for water or moisture in a fuse boxes (especially in a front one, where the SAM module lives), checked the charging system. Everything seems to be fine. OBD scanner shows only one malfunction code - something with a throttle body sensor. Do you have any ideas what can cause those problems? It might be a broken SAM module, but maybe there is something else that I can check before replacing SAM.
Regards,
MC
