Hi,
what doesn't actually work as there are a few different cures for this issue?
For instance there is usually a brown/white wire that is connected to the rocker cover stud on the rear right corner, this in turn has an earth braid that goes to the coil mounting bracket bolt. This earths the clocks and keeps the thing from going haywire.
Another common problem for totally dead clocks is the voltage regulator on the rear of the clocks. Plus check for signs of damage to the Blue plastic foil circuit board.
Usual suspect though is a poor connection on the actual plug to the clock unit. So take the whole assembly out out unplug the connector, clean the contacts on the foil and then, slide the ribbon off the plastic tab. Wrap a couple of turns of insulating tape around the tab to make it thicker, then replace the foil back over the tab and reconnect this should allow for better contact between the foil contacts and the connector it's self.
