1990 F-350 6.9 battery light flickering
- Thread starter Dubshot
- Start date
Compu Doc
Full Access Member
It would usually men that your having charging system issues, Have your alternator checked. It can be tested in he vehicle.
Brianedwardss
Registered User
Mine did that when one of the small wires going into my alternator got just the slightest bit loose.
icanfixall
Official GMM hand model
All of these diesel trucks have dual batteries. The signal wire may be loose on the alternater as posted above. I had my charging lite flicker on and off for about 8 months. I checked everything I could think of... started throwing parts at it.... No help.. finally at nite the lite was on so I started looking again. Flashlite in hand till I found the issue. The signal wire on the alternater had broken but... The wire was still connected to the metal connecter. How the copper wire broke between the plastic clamp and the metal sleeve is really kinda funny. So I cut off that connecter and installed another.... Had it not been for the darkness I would never have seen the arcing at the bad connection... thank you darkness....
homelessduck
Full Access Member
I had the same issue recently.. It was the signal wire. I tried crimping the end to make it tight again, but it was just old and kept loosening up.. So I tossed a new female connector on it, and it fixed the problem.
trasko
Registered User
I'm having this same problem on my '91 7.3L. Looks like one of the signal wires is fraying badly. Funny thing is that the battery light only comes on during hard acceleration. I figure an increased current finding it harder to make it through the compromised wire?
On a -- perhaps -- related note, my voltmeter doesn't work. The needle never moves off of the far left. Are these the wires that the voltmeter reads? Or.. from the wiring diagram in the chilton's manual it seems like maybe it's the wire coming out of the voltage regulator. I'm assuming that metal box bolted to the wheel-well on the pass. side is the regulator.
The truck has been like this since I got it about 1.5 years ago. There's no charging issue but I'd like the voltmeter to work.
On a -- perhaps -- related note, my voltmeter doesn't work. The needle never moves off of the far left. Are these the wires that the voltmeter reads? Or.. from the wiring diagram in the chilton's manual it seems like maybe it's the wire coming out of the voltage regulator. I'm assuming that metal box bolted to the wheel-well on the pass. side is the regulator.
The truck has been like this since I got it about 1.5 years ago. There's no charging issue but I'd like the voltmeter to work.
