Surprisingly, only found one thread on this in the archives. It points to a complete re-solder of the clock circuit board:

http://p-car.com/diy/clockrepair/

I don't have any warning lights coming on, which seem to accompany the clock stoppage -- my only symptom is that the clock and adjuster button stopped working for no apparent reason. The backlights work fine. Wondering if anyone has been through this and knows of a solution easier than re-soldering the circuit board, or whether this problem has a different cause entirely.

 

NP993,
I've removed and worked on several clocks. The lighting circuitry is separate from the movement. There are two root causes for the failure that I have come across, one being damaged solder pads that mount front mech and back pcb and the other being (depending on year) a miniature inline pcb fuse on the underside of the back pcb. Looks very much like a small diode. Continuity can be check with an ohmmeter on a DMM or DVM. If it's open, then just de-solder and replace with a standard fuse wire. Visually the front mech and back pcd looks as if it is just plugged together, this is not the case. The back pcb board can only be separated from the front half mechanism assembly by de-soldering the main feed pins (on the back pcb) which are hard mount points on the front of the clock. Solder wicking braid is best for this. Don't try to pry or force the back pcb from front as you will only damage the solder pads on the pcb. Hope that helps.
If you want, you can send it to me and I'll look at it.

Cheers,
Greg

 

My clock is a little wacky too. Adjuster works but the time is always off

 

Good info Greg!

 

Thanks Greg -- that's very interesting. I have a feeling it's going to turn out to be a problem with the fuse, as the problem showed up after I had removed and reinstalled the battery in my car -- figured it was just a coincidence, but perhaps not. I'll remove and investigate......appreciate your generous offer.

 

The adjuster button is cheap and can corrode easily (especially since it does not see alot of use)

Try some contact cleaner on it

 

Thing is, the clock itself doesn't work....would that be the case if just the button had malfunctioned?

 

Either the adjuster button works, doesnt work or wont shut off and the clock spins, it is possible that it is the cause of a blown fuse so check the fuse first..

 

Let me know what you discover. If you need help just PM me.
Cheers,
Greg

 

Can you show a pic of the fuse? I have the same problem but may not be able to identify the fuse. (Old geezer with bad eyes.)

 

Unfortunately, I didn't take a pic of the fuse since I repaired it before I sent it to Andreas for his metal handy work that produced an awesome solid aluminum desk clock. If you have it, (I say this because it depends on the year), it'll be on the underside of the visible side of the pcb shown below. The only way to remove the pcb is to de-solder the three adjacent main contacts that connect the movement mech and that back side pcb. They are next to light bulb #7 marked with V+ -. First, follow the + trace to the left and there should be another pad. Ohm out that pad between the gap and see if it's open. If it is, then you have a blown fuse.
See pic.

 

Maybe you can help me out here with 2 questions: my clock was not functioning in the car (964); it also wasn't functioning when directly connected to a 12v battery. Any idea what the issue could be?

In the mean time, I also bought a reconditioned clock; it works when directly connected to 12v, but there's seems to be an issue in the car: the permanent 12v seems out of order. The #11 fuse in the luggage compartment works fine; so do the interior lights. Any other option than to follow the 12v wire to see where the problem is?

Also, on the big connector, what is the color of the wire connecting to pin #30?

This is a fun but frustrating project at the same time...

I'd be grateful for any guidance