View Full Version : FZJ80 Charging issue

08-07-2009, 05:32 PM
I have an intermittent charge light that is giving me trouble. I first got it after driving 37 miles on a dirt road in the pouring rain. I figured it would go away once everything dried out, but no such luck. I pulled the alternator and battery and took to Autozone. They both tested ok. I spent quite a bit of time cleaning up the old battery with cleaner and wire brushes. I did the same to the battery box and the cables. I put it all back together the light is still mostly on but flickers off intermittently while driving. I figured the battery was cheaper, so I bought a new battery and put that in today. After ten minutes of driving the charge light is back on.

I figured I would see if anyone had any ideas as to what I might try before I replace an alternator that has tested ok. Is there anything specific to the 80 that I am missing? I know another possibility would be to replace the cables, but that appears to be a chore. They don't seem to be in any condition that would prevent them from charging the battery.

Chris Sutton
Golden CO

08-07-2009, 06:05 PM
Could be a grounding issue. Get a volt meter and measure the resistance from the neg plug on the battery to the chassis of the vehicle. It should be much less than 1 ohm. If not, then where the cable connects to the frame has a dirty or poor connection.

I always start with grounding before I continue on, half the time a wire came undone or loosened or is corroded

You didnt say what year you have, but you could also see if there are any codes set via the OBD Port

Good Luck

08-27-2009, 08:49 AM
I disconnected all of the grounds in the engine bay, cleaned them up and re-torqued them. I still got the charge light after a few minutes of driving. After that I really looked hard at replacing the battery cables, but there is so much going on with the hot side. I didn't want to mess with the various inline connections, fusible links, etc. I found a complete set of replacement cables, but they were $135 plus shipping. Needless to say I was hesitant, so I went back to the alternator.

The alternator said that it was made in Taiwan, so it didn't even look like it was a remanufactured Toyota unit. I read that you can rebuild them, so I thought I would give that a try. I took the thin shield off of the end along with a couple more pieces, but the case did not appear to come apart. I was thinking that maybe this one was not rebuildable. I figured I would get it re-tested somewhere else.

I took it to Checker and it still tested good. Based on the symptoms I figured there was something partially broken inside and was only failing to charge once everything got hot in the engine bay. I still felt a little wierd replacing an alternator that tested good, but they had one in stock and it was the only way to know for sure if the alternator was the problem. I got a Nippondenso remanufactured unit for $155 after tax.

I installed it and drove around most of the evening last night. Still no charge light, so I am betting it is finally fixed. I just wanted to post up this detail for anyone who is relying on the testing machines to rule out a bad alternator. Just because it tests good doesn't mean it is good.

Thank you for your help Romer.

08-27-2009, 10:19 PM
I would still take a look at the + cable from the alt to the battery. If you have a poor connection there your low charge light will go on. In my case it was a failed crimp connector at the alt that cascaded into more. :mad: