on my 1990,the speedo has quit working,usually after a few miles it will start working again and will stay workin till a day or two later,when it is not reading mph,the odometer is still counting miles , any ideas??
CK5
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Speedo working intermittently
- Thread starter snowdriver
- Start date
If the odometer is still reading, I would think that the problem is in th speedometer head. However, I have no help with what you may be able to do to fix it. Maybe there is a poor connection to the head, internally.
I've never had one of these apart, but I would guess that the odometer and speedo are driven by the same component...maybe a gear setup to power the odometer and speedo at the same time?
If anyone has had one apart, I'm certainly curious to hear how they work.
Odometer is gear driven, the speedometer is magnetic driven by the gears.
I have had this problem and I changed the whole speedometer.
Went out and checked my spare, can't believe I never took the time to look at one as closely as possible, I've certainly had them out more than a couple of times. Not much to see, PCB, the motor, the gears, pretty hard to get a good look inside. Couldn't find a video of someone disassembling these.
The trip odometer and actual odometer are both run by the electric motor, connected by a gearset. The back of the speedometer itself looks like a sending unit, so can certainly see why one or the other could quit working.
Couple of options I suppose, replace it if you can find a cheap spare, or talk with a speedometer shop to get it repaired. I've heard that getting speedometers repaired isn't always a stupid expensive endeavor.
Although, third option, I did notice that the speedometer appears to be connected to the PCB similar to how the other gauges are connected to the flex circuit...spring loaded metal "sockets". It may be possible that those are not making good contact? If you have to take the speedometer out, might not hurt to check/wiggle those contacts if possible, and see if it makes any difference. Be careful pulling the speedometer out, the plug attached to the PCB that comes off the flex circuit is pretty tight, and doesn't have a ton of slack. If I was going to try and pull the speedometer without pulling the entire cluster housing, I'd first get the fuel gauge out of the way, then make sure I could pry on that plug with a tool to get it loose.
I have not taken it out yet,but will in the next few days,will update
If it comes down to it I have a working speedo only.
Getting the speedo gauge out of a 1988 to 1991 square body truck is a pain. You have to disconnect the printed circuit board terminal end from the odometer motor circuit board, and then you can pull the speedo gauge out of the gauge housing. If the gauge itself is the problem you will have to send it to a company that specializes in repairing gauges because there are no aftermarket reproduction gauges for the 1988 to 1991 square bodies like there is for the older 1973 to 1986 square bodies.
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