Locker Lights staying on (1 Viewer)

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My diff locker lights are randomly staying on when I start the car even with the lockers off. Its very intermittent. Sometimes they go off like normal. Other times they stay on for a minute or two.

I tried replacing the locker switch, and that didn't work. Also, when they're in, if I flip the locker switch to "on" the lights go off. Anyone else had any issues like this? I'm wondering if the caps in my diff locker ecu are starting to go.

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ppc

M Go Blue
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Aug 18, 2003
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Nashville, TN
Yes it could be the locker ECU but the first thing I would look at when problems are intermittent are grounding issues.
 
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Will do. Any idea where the lockers are grounded?
It may not be a ground problem with you're locker system per say, but may in fact be a ground problem with the locker lights in the instrument panel. Get out your factory electrical trouble shooting manual and check all the grounds for the instrument panel to make SURE they are all clean, and TIGHT.

I've run into a problem like this before, the ground for the instrument panel came loose on a truck i owned. (a Chevy not my LC) That loose ground would sometimes cause the turn signal lights to light up for no reason, along with the oil, water temp, and alternator lights turning on, and off all on their own.

Once i found the instrument panel ground, cleaned and tighten it, i had no more problems with the lights acting like a Christmas tree. One thing i will tell you when i first started trouble shooting this problem, the lights would only do this every so often, but as the ground became looser over time, the lights did this more often and would stay on longer.
 
Joined
Jan 6, 2013
Messages
1,810
Location
Golden, CO
It may not be a ground problem with you're locker system per say, but may in fact be a ground problem with the locker lights in the instrument panel. Get out your factory electrical trouble shooting manual and check all the grounds for the instrument panel to make SURE they are all clean, and TIGHT.

I've run into a problem like this before, the ground for the instrument panel came loose on a truck i owned. (a Chevy not my LC) That loose ground would sometimes cause the turn signal lights to light up for no reason, along with the oil, water temp, and alternator lights turning on, and off all on their own.

Once i found the instrument panel ground, cleaned and tighten it, i had no more problems with the lights acting like a Christmas tree. One thing i will tell you when i first started trouble shooting this problem, the lights would only do this every so often, but as the ground became looser over time, the lights did this more often and would stay on longer.
Yeah that sounds exactly like what's happening to me. Thanks.
 
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So, I checked the grounds, and that made no difference. After looking at the EWD, it looked like it basically had to be the Diff Lock ECU. I unplugged the ECU and the stuck light went off immediately which confirmed my suspicion. I opened it up and saw no obvious damage, but I know that capacitors from this era do eventually dry out and cause issues. So, I replaced the only two capacitors on the board and that seems to have fixed the issue. The light turns off like normal every time. Unfortunately, this probably means almost every cap in the car is probably shot or well on its way...
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this probably means almost every cap in the car is probably shot or well on its way...
That was a good find, but Seeing as how many computers these trucks have. Replacing every capacitor would turn into a very time consuming pain in the ass.
 

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