Clock fix

[Tori]

Thought i'd share my clock fix with some of you that may have a bum clock. I'd done all the reading on them, and figured out how to get it apart, and what to look for. Most of the repair info was for the older style clocks, which didn't really apply to the clock in my '87 as it uses an electric motor.

One of the posts i read mentioned replacing the two capacitors on the printed circuit board.

My repair was easy and only cost $3.00. The hardest part was getting the thing apart, and putting it back together. (the black ring)

As far as troubleshooting, once i had mine apart, i put power and ground to it and could see the motor trying to work and could see no visible damage to the gears or other mechanism.

I removed these two capacitors:


The clock now works perfectly.

And installed two Radio Shack part #272-1028 capacitors:
**note, make sure you install them fully against the circuit board. you don't want them breaking the solder joints from vibration. I later went back and repositioned these, then clipped off the extended wires that went above the PCB. If you don't trim the wires they will ground out on the case.

[DRACO A5OG]

Nice :-)

[merlinfe]

Brilliant!

- Steve

[RSBob]

Since I have two dead ones, I will give it a shot. Thanks a bunch for posting.

[mhackney]

Not to hijack but I wanted to let folks know about a post I made for the capacitor fix for the clock in my 83 SC which has some tips/techniques for removing and replacing the bezel ring which might be applicable to Carrera clocks too.

[Tori]

Originally Posted by mhackney

Not to hijack but I wanted to let folks know about a post I made for the capacitor fix for the clock in my 83 SC which has some tips/techniques for removing and replacing the bezel ring which might be applicable to Carrera clocks too.

Excellent write up ! I hadn't seen your post when i was searching. It appears we have the same clock too.

[Steve W]

Old dried out capacitors are what typically cause the clock to eventually fail. Heat in the car causes the electrolyte in the caps to dry out. Service life of a capacitor is inversely proportional to the heat it is exposed to. A cap rated with a 5000 hour service life at 105C only needs to see that temp for 4 hours a day, 300 days a year, for four years to exceed that. The original caps are IIRC German Roederstein high temperature caps (now owned by Vishay). Radio Shack and typical caps are rated up to 105 degree C which if you consider how hot an interior gets in a car parked in the sun it is preferable to use the highest temp cap you can source. And considering most of these low quality caps are made in China, the claimed rating and service life is questionable. I'd recommend using brand name high temp caps such as Japanese Nichicon caps rated at 150 degree C.

http://www.mouser.com/ProductDetail/Nichicon/UBX1H101MPL/

An interesting story I remember from a few years ago, hundreds of millions of electronic devices and computers failed early due to failing capacitors used in their manufacturing, including PCs from Abit, IBM, Dell, Apple, HP, and Intel. The Chinese/Taiwanese were conducting industrial espionage to steal and copy the secret water based electrolyte formula used to manufacture caps in order to undercut the Japanese. Apparently a materials scientist from Rubycon in Japan left the company taking with him the secret water-based electrolyte formula used in Rubycon's capacitors, to work for a Chinese company. Either by design or otherwise, some staff members defected this company and took with them a incomplete or flawed version of the formula and tried to market it to many of the cap manufactures in China and Taiwan, either that or a purposely flawed formula was intentionally spread around otherwise, which then perpetrated an entire industry of flawed inferior capacitors. The formula lacked important proprietary ingredients where were essential to the long term stability of the capacitors. Which is why you see for example wall warts and PC power supplies fail in anywhere from 1.5 -3 years. Because of that, to this day many brand name PC motherboard manufacturers market their higher end products as using Japanese capacitors.