Hi all,
I need some electrical help. I have a 1971 fj40 with the stock engine and stock 40 amp alternator. My problem is I can't run my headlights and heater at the same time without discharging the battery. When I turn on the headlights, my ammeter drops to just above 0. If I turn on the heater with the headlights, it drops quite a ways into the negative on the ammeter. Just the heater alone will also drop the ammeter to just above 0. A normal reading on my ammeter is about halfway up on the positive side without the heater or headlights on.
Things I have done:
1. Had alternator tested at auto parts store - good
2. Checked connections and cleaned any that looked questionable, including the fuse box.
3. Checked all the grounds that I can find - I even replaced the ground wire from the starter to the frame and both battery cables.
4. Ohmed out all the connections I can find and/or get to, to make sure nothing is shorting or grounding out.
5. Everything works, so I started disconnecting things (lights, horn, taillights, etc) one at a time looking for a possible short.
6. Checked voltage with a meter at all lights and connections. All were basically at 13 volts. All lights, gauges and accessories seem to be working fine.
So far, nothing I have done has worked. I realize that I only have a 40 amp alternator, but nothing has been added to this rig to require more amps (i.e. no winch, stereo, etc). It is still stock. Therefore, the stock alternator should work fine. Right? I could always put in a higher amperage alternator, but it seems that would only mask the problem (or not fix it at all). I'm assuming (I know, I know) that this is a grounding issue. I've checked the grounds that I can think of (battery, starter, taillights, marker lights).
What else should I do? Are there other grounds that are somewhat hidden? Any obvious spots to look? Right now I'm open to suggestions. I have spent probably 20 hours looking for this problem, and I'm about to the point of taking it in to someone to track down for me. I just hate having to pay someone else for something I can do myself. Please help.
Thanks,
Kyle
I need some electrical help. I have a 1971 fj40 with the stock engine and stock 40 amp alternator. My problem is I can't run my headlights and heater at the same time without discharging the battery. When I turn on the headlights, my ammeter drops to just above 0. If I turn on the heater with the headlights, it drops quite a ways into the negative on the ammeter. Just the heater alone will also drop the ammeter to just above 0. A normal reading on my ammeter is about halfway up on the positive side without the heater or headlights on.
Things I have done:
1. Had alternator tested at auto parts store - good
2. Checked connections and cleaned any that looked questionable, including the fuse box.
3. Checked all the grounds that I can find - I even replaced the ground wire from the starter to the frame and both battery cables.
4. Ohmed out all the connections I can find and/or get to, to make sure nothing is shorting or grounding out.
5. Everything works, so I started disconnecting things (lights, horn, taillights, etc) one at a time looking for a possible short.
6. Checked voltage with a meter at all lights and connections. All were basically at 13 volts. All lights, gauges and accessories seem to be working fine.
So far, nothing I have done has worked. I realize that I only have a 40 amp alternator, but nothing has been added to this rig to require more amps (i.e. no winch, stereo, etc). It is still stock. Therefore, the stock alternator should work fine. Right? I could always put in a higher amperage alternator, but it seems that would only mask the problem (or not fix it at all). I'm assuming (I know, I know) that this is a grounding issue. I've checked the grounds that I can think of (battery, starter, taillights, marker lights).
What else should I do? Are there other grounds that are somewhat hidden? Any obvious spots to look? Right now I'm open to suggestions. I have spent probably 20 hours looking for this problem, and I'm about to the point of taking it in to someone to track down for me. I just hate having to pay someone else for something I can do myself. Please help.
Thanks,
Kyle