In trying to diagnose a non working power antenna, I used a screw driver to pry off the 5 pin antenna plug in the trunk, saw a spark. Checked fuses and sure enough fuse #2 is blown. Replaced fuse #2 and all accessories on that fuse seems to be working- courtesy light, trunk light, hazard lights, cluster warning lights except one that I find days later- a dead clock which has been running fine prior.

How can shorting / blowing a fuse kill the clock?

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

On a 123 pretty much everything that stays on when the key is off runs off fuse 2.

When you pried off the plug you shorted the constant hot lead that runs the antenna down after you shut off the car. Maybe you created a surge that was enough to kill the electronic clock. Hopefully it was just the capacitors and you can get it running again.

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The OM 642/722.9 powered family
Still going strong
2014 ML350 Bluetec (wife's DD)
2013 E350 Bluetec (my DD)

both my kids cars went to junkyard in 2023
2008 ML320 CDI (Older son’s DD) fatal transmission failure, water soaked/fried rear SAM, numerous other issues, just too far gone to save (165k miles)
2008 E320 Bluetec (Younger son's DD) injector failed open and diluted oil with diesel, spun main bearings (240k miles)

1998 E300DT sold to TimFreeh
1987 300TD sold to vstech

Maybe a surge killed the clock also but right now C104 pin 1 has no power yet everything else on fuse #2 works except the clock. C104 pin 4 has power with key on so I wrapped a bare wire shorting 1 and 4 on the male C104 mating plug, plugged connector together, turned on the key and clock is still dead.

How is the C104 mounted to the bracket? It feels like it is clipped on and should slide off but I can't get it off and don't want to break something.

Edit: Pulled cluster out and the red/yel wire to the clock has power. Something got screwed at C104 pin 1 wiring.

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Pulled cluster, replaced both electrolytic capacitors- clock works again! Took pics will post later.

Moral of the story: Don't pry the power antenna connector with a screwdriver! Use something insulated. I was actually trying to look for something insulated to pry with but couldn't find anything so used a screwdriver that was handy. Big mistake!

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Clock module removed. No burned traces.



Replaced both 100 uf caps ( they both checked bad on the ohm meter) with ones taken from old car cell phone chargers- they are the 2 black ones and are 220 uf 16 V, higher than the ones it replaced. It's ok since they are used for bypass filtering and not for timing purposes. I didn't want to run to Radio Shack nor did I want to spend money if I already have them.

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

The clock is keeping time just fine so I consider it fixed.

The antenna switch was not getting the control signal from the radio so the power antenna never worked. It had an Alpine radio from the PO and the original connector was cut and spliced before I installed the current bluetooth radio. Instead of tracing the BU (blue) antenna control wire which would have been a major job ripping the console apart, I added a wire from the radio directly to the antenna switch and the antenna works now.

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked