idM1028
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- Somewhere in Nebraska
I've been having problems with the GEN2 light working properly on my M1028. Now, before anybody jumps in saying replace the bulb, or check the fuse, or check the exciter wire, here's what I've already accomplished:
Initially the light wasn't coming on at all. I replaced the bulb and the 24V fuse in the truck. My voltage readings at the fuse and the plug for the instrument panel were around 24V. I can't remember the exact numbers, but it was around 24V for both. I checked the red and brown wires for the voltage regulator on GEN2 and both were also around 24V. I also bypassed the GEN2 relay with a jumper wire. Connecting the brown and red ground wire for the bulb and the black ground wire for the relay made the GEN2 light nice and bright. Disconnecting it caused it to go out, so I figured it had to be a bad relay. I replaced the relay and the problem persisted. I then checked the pink and black hot wire for the relay from the fusebox. I got a reading of 12V even between it and the ground wire. Thinking it might be the alternator I took it out and had it tested today. On the bench it put 14.6V and 80, pushing 90 amps so I went and put the alternator back in the truck. Now with the key on, the GEN2 light is lit, but dim. When starting the truck, it gets nice and bright and goes dim again once the truck is running. I also tried swapping relays since I was a little leary of the new one being that its Chinese made. No dice. RPM also doesn't seem to affect the brightness. It doesn't get dimmer the faster I go. ????
What else could I possibly check? It seems like I've got all the bases covered. I still think it might be the relay. Is there any way to pull the relay out and check it?
Initially the light wasn't coming on at all. I replaced the bulb and the 24V fuse in the truck. My voltage readings at the fuse and the plug for the instrument panel were around 24V. I can't remember the exact numbers, but it was around 24V for both. I checked the red and brown wires for the voltage regulator on GEN2 and both were also around 24V. I also bypassed the GEN2 relay with a jumper wire. Connecting the brown and red ground wire for the bulb and the black ground wire for the relay made the GEN2 light nice and bright. Disconnecting it caused it to go out, so I figured it had to be a bad relay. I replaced the relay and the problem persisted. I then checked the pink and black hot wire for the relay from the fusebox. I got a reading of 12V even between it and the ground wire. Thinking it might be the alternator I took it out and had it tested today. On the bench it put 14.6V and 80, pushing 90 amps so I went and put the alternator back in the truck. Now with the key on, the GEN2 light is lit, but dim. When starting the truck, it gets nice and bright and goes dim again once the truck is running. I also tried swapping relays since I was a little leary of the new one being that its Chinese made. No dice. RPM also doesn't seem to affect the brightness. It doesn't get dimmer the faster I go. ????
What else could I possibly check? It seems like I've got all the bases covered. I still think it might be the relay. Is there any way to pull the relay out and check it?
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