Coolant Temperature Indicator Test
- If coolant temperature indicator illuminates with engine running (not overheated), remove connector to coolant temperature switch/sender. If indicator turns off, replace coolant temperature switch/sender.
- If indicator remains illuminated, check Dark Green wire between coolant temperature switch/sender and ignition switch for short to ground. Ensure printed circuit has no cracks or flaws, and mates correctly with its connector.
- If coolant temperature indicator does not illuminate while starting engine (and bulb is okay), ground Dark Green wire at terminal "C" of connector C1 at ignition switch. If indicator illuminates, circuit is okay. Replace ignition switch. If indicator does not illuminate, check Dark Green wire and printed circuit for open circuit.