clock stuck on 1:00

Grasping at straws but maybe the buttons stuck down and there is no electrical prob?

You are correct tho, 1 ground (-), 1 hot +12v hot all the time (running time), 1 +12v to illuminate when the key is on, and 1 wire that dims it when the head lights are on. So 4 wires total.

Either, you lost the ground (unlikely) cause it does light up when the key is on, you lost the +12v hot all the time (possible but unlikley), the buttons stuck or the clock died.

You'll have to pull it to test power. The dash panel comes out easy do a search, but I'd play with the left button for minute before you do this.


Edit: theres a crystal oscillator on the clock and it might have died which could result in stopping time! Thus time travel is not an option!:thumbsdow so you need a new clock if gnd and the +12v hot are OK.

from the back
===============================
(ILL) . . (+12vhot)

(dim) . . (Gnd)
===============================

This comment implies its on th dome light circuit.

Sorry, don;t have schematic for the car - From the GEN 3 Body Electrical pg 159 we have this.

No Tic Talk >Clock
(a) Check that the battery positive voltage is 10 – 16 V. If voltage is not as specified, replace the battery.
(b) Check that the DOME fuse is not blown. If the fuse is blown, replace the fuse and check for short.
(c) Troubleshoot the clock as follows.
HINT: Inspect the connector on the wire harness side.

CLOCK LOSES OR GAINS TIME

(a) Check that the battery positive voltage is 10 – 16 V. If voltage is not as specified, replace the battery.
(b) Inspect the error of the clock. Allowable error (per day): ± 1.5 seconds. If the error exceeds the allowable error, replace the clock.
(c) Check that the clock adjusting button is sticking in position and has failed to return. If the button is not returned, repair or replace the clock.
(d) Troubleshoot the clock as follows.
HINT: Inspect the connector on the wire harness side.


Hint: camrystuff.com