2007 Sprinter, build date 10/07. Chassis Cab setup with box on back. Diesel.
It first started a week ago. Started the van, battery stayed on until I revved the engine. Happened again yesterday. Today while driving the battery light came on, then the seat belt light came on... I always where my seat belt. Started looking like Christmas on the dash, both lights alternating back and forth, then nothing for a bit, then flashing lights randomly. I got out my voltage meter and hooked it up. While driving normally system voltage is at 13.3vDC. When either the seat belt or battery light turns on, drops to battery voltage, 12.8 - 12.0 depending on how long it hasnt been charging.
Sometimes the seat belt light comes on, nothing charging, then goes off, starts charging again. Sometimes the battery light comes on, stops charging, then it always turns off, then the seat belt light turns on, still not charging, then if the belt light turns off it will start charging again. The battery light never just turns off, it always switches to the seat belt light first. I've noticed I can pretty much always get it to stop charging under heavy acceleration, although it will randomly stop charging while cruising or decelerating. If I'm idling no amount of fast or slow revving will make the light come on. Seat belt on or off doesnt effect the situation. I can hear what sounds like a relay clecking under the dash as charging kicks in and out.
Normally I'd just go for the alternator, but seems odd that the seat belt light is 'involved' in the problem. Just for kicks I checked most of the reachable connections under the hood, everything was dry and properly seated. I'm wondering what the relay has to do with anything. I have no wiring diagrams to look over at the moment.
Whatcha think?
It first started a week ago. Started the van, battery stayed on until I revved the engine. Happened again yesterday. Today while driving the battery light came on, then the seat belt light came on... I always where my seat belt. Started looking like Christmas on the dash, both lights alternating back and forth, then nothing for a bit, then flashing lights randomly. I got out my voltage meter and hooked it up. While driving normally system voltage is at 13.3vDC. When either the seat belt or battery light turns on, drops to battery voltage, 12.8 - 12.0 depending on how long it hasnt been charging.
Sometimes the seat belt light comes on, nothing charging, then goes off, starts charging again. Sometimes the battery light comes on, stops charging, then it always turns off, then the seat belt light turns on, still not charging, then if the belt light turns off it will start charging again. The battery light never just turns off, it always switches to the seat belt light first. I've noticed I can pretty much always get it to stop charging under heavy acceleration, although it will randomly stop charging while cruising or decelerating. If I'm idling no amount of fast or slow revving will make the light come on. Seat belt on or off doesnt effect the situation. I can hear what sounds like a relay clecking under the dash as charging kicks in and out.
Normally I'd just go for the alternator, but seems odd that the seat belt light is 'involved' in the problem. Just for kicks I checked most of the reachable connections under the hood, everything was dry and properly seated. I'm wondering what the relay has to do with anything. I have no wiring diagrams to look over at the moment.
Whatcha think?