-
Dash light rheostat
The original rheostat in the dash burned out about a year ago. replaced with with a new one, same specific and manufacturer. This last weekend I was driving the bus and I thought I would turn up the lights and when I touch the knob it was so hot that I burned my fingers. Disconnected the unit from wiring harness and noticed that the dash vinyl near it was burn to carbon. Doesn’t throw a beaker in the drivers side electrical panel.
Any ideas on what the problem is and what to look at?
-
12 Replies
-
Hi Greg,
did you ever figure out what the problem was? Looks like someone wired a large current consumer into your dash light circuit. Probably the reason why your first unit burned out. Could also be someone put in 12V bulbs vs 24V bulbs.
I was using search to find any post on dash rheostats. My dash lights are flickering on-off and I’m suspecting the rheostat or associated supply/ground connections. Just wanted to see what other people had encountered.
Gerald
-
I ended up taking the reostat out and just connection the two wires together and I have had no issues with the CB being trip. Of course I always have a full bright dash light, but the lighting is so poor that I general had it turned all the way up. I did buy another reostat but have decided if I will putt it in. May do so just to fill the hole.
-
Or just put in a toggle switch so you have full on and full off. I like to turn down all the dash lighting at night when I’m backing up or working in the close quarters like a Wal-Mart parking lot. Keeps the instrument and panels from reflecting on the glass.
-
I recently changed out all my brake, hazard, back-up and tailoghts to LEDs. All worked fine but n the hangar. Once on the road issues arose. Left turn indicator displayed correctly on dash. Right turn indicator also worked but on dash displayed as four way flasher and brake indicator flashed on and off. Has anyone experienced this issue.
-
Greg,
Did you ever get this rheostat issue resolved? I just changed my dash bulbs to LED and now the rheostat is getting hot. (115 degrees) Im wondering if the rheostat was bad causing the original incanedescent bulbs to be dim or the LED and rheostat dont like each other. Any insight from the electrical savy crowd would be appreciated. jeff
-
I wonder if Tommy Duhon solved his problem.
Jeff: What about the grounds? Did you check all the grounds?
-
Hi Dick,
Good thought. After reading your post I went out and checked the grounds and all seem to be good. I have gathered from reading that LED bulbs need a PWM type dimmer/rheostat. I am looking for one now. I found some on Amazon with the correct specs but they are only $2 or 4 for 9$. Not sure how good those would be. If anyone knows a source for a higher quality pwm rheostat please let me know Thanks, jeff
-
I switched my dash lighting to LED and was having troubles too.
I called PrevostPass and after checking everything they advised me to remove
the rehostat. Everything working fine now.
-
I once inserted a build so that when the turn signal was on that I back fed power to the running light circuit making it seem like the emergency flashers were on. Double check the culprit by removing turn signal bulbs on the side in question until the issue goes away. And then carefully insert the build correctly. Worked for me…
Elliot
-
Quick update on my hot rheostat. I ordered a new pwm rheostat that required the light feed positives as well as grounds to run through the dimmer. (Known as a “low side” dimmer). This type caused the gauges that have a sending unit to fluctuate because the lights use the same ground as the ground reference for the senders. I scrapped that one and ordered a pwm “high side” dimmer which only uses the positive wire for dimming. My issue is resolved and i am enjoying my bright instrument panel. I hope this helps someone down the line jeff
2000 Featherlite H3-45
2024 Jeep Grand Cherokee
Leesburg, FL -
My dash dimmer rheostat on a 97 XL is flickering or off. Prevost P/N 562489 or Pollak P/N 32107. It is only a 2 wire rheostat dimmer. Prevost has a replacement kit which requires 3 wires. P/N 069136 however, no dealer has it in stock.
Jeff, what is this “high side” dimmer or rheostat that worked for you? It sounds like it is a 2 wire device similar to the original. Do you have a part number or supplier? Is there a truck part that can be substituted? It is 24 vdc.
Thank you
Roger
2000 Featherlite H3-45
2024 Jeep Grand Cherokee
Leesburg, FL -
Be careful with the ground for the dash. Had the bus air dash unit go bad. Prevost Winter Garden replaced it,but mistakenly put a different one in that had different grounding. It back feed through the dash ground and wiped out most of the gauges and made a few alarms (low air and tag axle up) stick in the on position.
Prevost Winter Garden replaced the dash at there expense but had to install a used one because new ones are not available for my vintage.
Chuck
Log in to reply.