SL/R129: JBRUM
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1999 sl500
JBRUM
I HAVE A 1999 SL500 THAT STOPPED DEAD WHILE BEING DRIVEN. PULLED OVER ON SIDE OF ROAD AND THE CAR WILL NOT TURN OVER OR EVEN TRY TO START. TALKED TO MECHANIC AND HE SUGGESTED REPLACING THE BATTERY DUE TO ONLY READING 12.1 VOLTS. BATTERY HAS BEEN REPLACED AND NOTHING HAS CHANGED. WHEN THE KEY IS PUT IN IGNITION AND TURNED TO POSITION THREE, ALL LIGHTS ON DASH LIGHT UP. PLEASE TELL ME WHAT'S WRONG. JBRUM
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Joined: Jan 2006
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From: Atlanta, unfortunately
'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
12.1 volts is entirely adequate to start the engine. I suggest never taking your car back to the mechanic who changed the battery unless it is to change a water pump or some other basic task.
Either your engine computer or ignition switch may be faulty, or you could have a blown fuse.
Among the computers under a cover in the right-rear engine compartment is one know as the "Base" module. There are several fuses installed atop the module. Check those, since one of them powers the engine computer. I think they must be okay, but also check the "Maxi" (large) fuses in the main fuse box.
If the fuses are all good, then take the car to a competent independent shop that is equipped with Mercedes "Star Diagnosis" to discern whether the ignition switch or engine computer could be at fault.
Either your engine computer or ignition switch may be faulty, or you could have a blown fuse.
Among the computers under a cover in the right-rear engine compartment is one know as the "Base" module. There are several fuses installed atop the module. Check those, since one of them powers the engine computer. I think they must be okay, but also check the "Maxi" (large) fuses in the main fuse box.
If the fuses are all good, then take the car to a competent independent shop that is equipped with Mercedes "Star Diagnosis" to discern whether the ignition switch or engine computer could be at fault.
