by veefre Wed Jun 10, 2015 1:12 pmAs I was driving home the other night after viewing a spectacular sunset in the hills on the hottest day in the past few months, I noticed that the instrument panel lights were out. It was rather disconcerting, not knowing what speed I was actually traveling. The turn signals and warning lights still worked, just not the illumination to see the speedometer as well as for some auxiliary gauges (water temp, oil pressure). I made it home and set about trying to figure out what this new problem was. Replaced all the suspect fuses, to no avail.
The next day with more light to work by, I traced the wiring (thanks to a full color wiring diagram gleaned from links in this forum) and was able to identify a gray wire as that which leads to the panel lights. But it didn't help that due to a full exterior and interior body painting before I got the van, a lot of the wires under the dash were all the same color - turquoise. But I was able eventually to see that the gray wire to one of the panel lights also fed the illumination ring for the cigarette lighter and the aux gauges.
I suspected perhaps that the headlight switch, which controls the panel lights, might be the problem. Removing it was no big deal. But then I got the bright idea that maybe something internal was wrong. Naturally as soon as I removed the metal bracket that forms one side of the switch, the thing nearly exploded in springs and brass contacts and such. Luckily I was eventually able to use a zip tie to hold things together when I reinstalled the bracket, and the switch resumed its normal operation. But that of course did nothing to fix the lighting issue.
After more fuse replacement and doping it silicon grease... I decided it was time to peek - for the first time - behind the fuse block cluster. Sure enough, there was ample corrosion of the contacts under the fuse blockfrom windshield dripping on that corner of the dash, especially on the one underside connection that feeds the panel lights.
From there I start to feel a bit dumber than usual. The connectors are very nice brass push on types. In my effort to dismantle them, I wound up prying them off. Later on, I learned that all it takes is a little press on a hole in the middle to release a built-in catch. But it was too late for the two female connectors I wound up destroying. I replaced them with more standard connectors, which aren't as nice and probably not as secure as the originals, but it was the best I could do. They do fit tight, though. I wound up lightly sanding all the connections with Scotchbrite to remove corrosion and coating everything with silicon grease (the clear kind) to help prevent future corrosion. I made a mental note to pull the windshield and fix the leaks as well as replace the new connectors with ones that lock in place like the originals. If I can find them.
The good news is that this final work on the back side of the fuse block fixed the panel lighting problem, at least for the instrument cluster. A test drive revealed though that the aux lights still were not illuminating properly. Eventually I figured that the vampire tap a previous installer had used was for a larger wire gauge than that it was connecting. I pried it off and got the proper size tap (red) and that fixed that, finally.
Now the van has instrument panel lights again.
Of course, the typical meltdown of the dome light wiring was evident when I pulled the headlight switch. Orange wire, melted to a crisp. No problem, because the dome light was disconnected long ago. Made a mental note to run a new, heavier gauge wire to a new dome light - probably some sort of nifty LED affair - in future. Probably bypassing the headlight switch and using an add-on under-dash toggle switch instead. It would be very nice to have some sort of interior lighting on this van. Flashlights and lanterns just don't quite make it.
Did some searching for original style wiring connectors, but so far unsuccessful. Found some in the 18 gauge size, but the back of the fuse block also requires 12 gauge connectors (one or two of which I had to replace after I manhandled them).
As an aside, I've noticed a discrepancy between the service manual and reality when it comes to this van's instrument panel illumination. The manual shows two light bulbs for each big gauge on the panel. Which would be nice and proper. However, despite some determined and repeated searching and skinned knuckles, I've pretty much established there is only one light per gauge, set off to the lower outside. It is enough to tell what's going on, but for example the right side of the speedo is rather dim without the extra light. Anybody else notice the same thing?
The next day with more light to work by, I traced the wiring (thanks to a full color wiring diagram gleaned from links in this forum) and was able to identify a gray wire as that which leads to the panel lights. But it didn't help that due to a full exterior and interior body painting before I got the van, a lot of the wires under the dash were all the same color - turquoise. But I was able eventually to see that the gray wire to one of the panel lights also fed the illumination ring for the cigarette lighter and the aux gauges.
I suspected perhaps that the headlight switch, which controls the panel lights, might be the problem. Removing it was no big deal. But then I got the bright idea that maybe something internal was wrong. Naturally as soon as I removed the metal bracket that forms one side of the switch, the thing nearly exploded in springs and brass contacts and such. Luckily I was eventually able to use a zip tie to hold things together when I reinstalled the bracket, and the switch resumed its normal operation. But that of course did nothing to fix the lighting issue.
After more fuse replacement and doping it silicon grease... I decided it was time to peek - for the first time - behind the fuse block cluster. Sure enough, there was ample corrosion of the contacts under the fuse blockfrom windshield dripping on that corner of the dash, especially on the one underside connection that feeds the panel lights.
From there I start to feel a bit dumber than usual. The connectors are very nice brass push on types. In my effort to dismantle them, I wound up prying them off. Later on, I learned that all it takes is a little press on a hole in the middle to release a built-in catch. But it was too late for the two female connectors I wound up destroying. I replaced them with more standard connectors, which aren't as nice and probably not as secure as the originals, but it was the best I could do. They do fit tight, though. I wound up lightly sanding all the connections with Scotchbrite to remove corrosion and coating everything with silicon grease (the clear kind) to help prevent future corrosion. I made a mental note to pull the windshield and fix the leaks as well as replace the new connectors with ones that lock in place like the originals. If I can find them.
The good news is that this final work on the back side of the fuse block fixed the panel lighting problem, at least for the instrument cluster. A test drive revealed though that the aux lights still were not illuminating properly. Eventually I figured that the vampire tap a previous installer had used was for a larger wire gauge than that it was connecting. I pried it off and got the proper size tap (red) and that fixed that, finally.
Now the van has instrument panel lights again.
Of course, the typical meltdown of the dome light wiring was evident when I pulled the headlight switch. Orange wire, melted to a crisp. No problem, because the dome light was disconnected long ago. Made a mental note to run a new, heavier gauge wire to a new dome light - probably some sort of nifty LED affair - in future. Probably bypassing the headlight switch and using an add-on under-dash toggle switch instead. It would be very nice to have some sort of interior lighting on this van. Flashlights and lanterns just don't quite make it.
Did some searching for original style wiring connectors, but so far unsuccessful. Found some in the 18 gauge size, but the back of the fuse block also requires 12 gauge connectors (one or two of which I had to replace after I manhandled them).
As an aside, I've noticed a discrepancy between the service manual and reality when it comes to this van's instrument panel illumination. The manual shows two light bulbs for each big gauge on the panel. Which would be nice and proper. However, despite some determined and repeated searching and skinned knuckles, I've pretty much established there is only one light per gauge, set off to the lower outside. It is enough to tell what's going on, but for example the right side of the speedo is rather dim without the extra light. Anybody else notice the same thing?
