In Dash Battery Voltage meter jumping

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

May 11, 2011
Oakland, Ca
Hello all!
This is my first posting so please forgive me if I am not detailed enough. I recently purchased a 89 FJ62. For starters, I love this vehicle. I had to put nearly 1500.00 dollars into this vehicle just to stop the leaks....and wouldnt you know it, the check engine light comes on two days later. The code its throwing is code 11 momentary interruption in power supply to ECU. Ive taken it to several mechanics and no one can tell me where this is coming from. Everyone simply wants to start throwing parts at it. Being out 1500 already i am reluctant to do so without even fixing the problem. The in dash battery voltage meter is jumping back and forth occasionally and when rolling down the window with the lights on it nearly drops to 0 but idles fine. The other day the truck was fine the RPM was ideling at 1000 and I turned on the lights and the truck voltage dropped 0 stalled and came back on. I had the alternator check and was told it is fine and charging the battery.
Any ideas. Thank you in advance:steer:
Do the wiggle test at both ends of the wire. Chances are, there the wire is not making a solid connection.
The in dash voltmeter dipping down a little in time with the turn signals is normal. The other problems are not. My recommendation is that you purchase a Repair Manual and become your own mechanic for most things. Maintenance bills will kill you if you don't These are older vehicles that require somewhat steady maintenance, especially in the first year or two after you buy it.

The first thing I would do is carefully inspect all the wiring around any work that was done by your mechanic to stop the leaks. Look for wires or connectors that are broken or cracked. It's possible something was disturbed during the work that was done. I would also check the battery terminals for corrosion. Check all the wires that connect to the + terminal of the battery. These are the fusible links. Make sure there is no evidence of corrosion or broken wires or connectors. The fact that you are momentarily losing contact with the battery would imply a bad connection. As long as your battery is maintaining it's charge, your alternator is probably doing it's job. I'd poke around looking for a corroded or broken connection.
Welcome to MUD.

I have to 2nd the motion of learning how to do all of this work on your own. Getting paid help for some things makes sense no and again, but for the most part if you don't turn a wrench you better have deep pockets.

As for your issues, it sounds like a loose connection or even a bad ground. When you use power ie. power windows, mirrors, turn signals you should see the gauge dip a tiny bit, but I would say it would still be above 12V. The dropping way down and stalling the vehicle is not good. I played with a lot of older VW's years ago and they sometimes had a similar problem. The majority of the time it was ground related. Make sure the connections are good and that you don't have corroded grounds. Battery terminals should be clean and if they are not...clean them.

Good luck with you problem. You might want to finish your profile details, especially location. There may be a fellow 62 owner in the area that is knowledgeable enough to help solve your issue in person.


Users who are viewing this thread

Top Bottom