SL/R129: Electrical Problems
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R129
Electrical Problems
Hi everyone I am having troubles getting my dad's 2001 SL up and running correctly after a prolonged time with a flat battery.
Stereo, electric seats and wing mirrors are not working. However the seats did work once but not do not work again. I have checked all the fuses under the bonnet (hood) and all seem fine. The car was fine when parked up a while ago. Any help would be appreciated. Thank you.
James
Stereo, electric seats and wing mirrors are not working. However the seats did work once but not do not work again. I have checked all the fuses under the bonnet (hood) and all seem fine. The car was fine when parked up a while ago. Any help would be appreciated. Thank you.
James
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From: Eastern Kansas
94 SL 600, 98 993, 89 XJS Conv., 85 Daimlier Princess 16 Hybrid Lincoln 16 Chevy crewcab
So, the engine runs?
Did you use the radio code to reset the stereo system ( applies to older Benz, not sure about all R 129's )
Was the dead battery replaced or in vehicle charged?
Did you use the radio code to reset the stereo system ( applies to older Benz, not sure about all R 129's )
Was the dead battery replaced or in vehicle charged?
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R129
I was wondering if there is some way of a reset of the electrical system?
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From: Atlanta, unfortunately
'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
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R129
Hello, Yes I can get a Mulitmeter from work no problem. Thank you for any input bobterry99.
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From: Atlanta, unfortunately
'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
If you remove the fuse box cover and expose the relays behind the row of fuses you will probably see a white relay -- the Comfort Features (CF) relay.
I would see if the CF relay is energizing. Have one person touch the relay while another turns the ignition key from position 0 to position 1 and back to feel for its contacts closing. Repeat the test by opening and closing a door with the key removed.
If you reply back with the result of that test I can suggest further troubleshooting steps.
I would see if the CF relay is energizing. Have one person touch the relay while another turns the ignition key from position 0 to position 1 and back to feel for its contacts closing. Repeat the test by opening and closing a door with the key removed.
If you reply back with the result of that test I can suggest further troubleshooting steps.
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R129
If you remove the fuse box cover and expose the relays behind the row of fuses you will probably see a white relay -- the Comfort Features (CF) relay.
I would see if the CF relay is energizing. Have one person touch the relay while another turns the ignition key from position 0 to position 1 and back to feel for its contacts closing. Repeat the test by opening and closing a door with the key removed.
If you reply back with the result of that test I can suggest further troubleshooting steps.
I would see if the CF relay is energizing. Have one person touch the relay while another turns the ignition key from position 0 to position 1 and back to feel for its contacts closing. Repeat the test by opening and closing a door with the key removed.
If you reply back with the result of that test I can suggest further troubleshooting steps.
White relay (on left hand side of car when standing in front of vehicle) as in pic I can definitely feel actuating when doors opened and closed with ignition key out of car. Windows pull down and up when opening and closing.
With the key switching from position 0 too 1. I can't say for 100% as they all actuat at the same time. But I think so.
Thanks again for your time.
James.
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From: Atlanta, unfortunately
'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
With the relay energized check for voltage on fuse #21. On a U.S. car that supplies power to the mirror and seat controllers, and probably does so on your car as well.
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R129
Cheers
James
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R129
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From: Atlanta, unfortunately
'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
Either a power source to the CF relay is interrupted by a wiring problem, or the CF relay has a blown diode that you can easily repair. To verify the problem is the relay remove it and using the diode-check function of a multimeter check between pin 4 (+) and pin 5 (-) of the relay. If the diode is bad the voltage will be infinite. As an alternative to that check you could remove the relay and measure the voltage between sockets #4 and #5 of its electrical connector. With key on you should have 12 volts, and this would imply that the CF relay is faulty.
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R129
Either a power source to the CF relay is interrupted by a wiring problem, or the CF relay has a blown diode that you can easily repair. To verify the problem is the relay remove it and using the diode-check function of a multimeter check between pin 4 (+) and pin 5 (-) of the relay. If the diode is bad the voltage will be infinite. As an alternative to that check you could remove the relay and measure the voltage between sockets #4 and #5 of its electrical connector. With key on you should have 12 volts, and this would imply that the CF relay is faulty.
Thanks everyone for your time and especaly Bobterry99.
