Use a volt meter or a test light. With the headlights on check or voltage on both sides of the inst lamp fuse (4th from bottom). If you have voltage- check the cluster ground. If no voltage- check for voltage on the right side of the stop/tail lamp fuse (bottom). If you have voltage- either the light switch is bad or you have a bad (lose burned corroded) connection at the light switch orange wire or green wire. If no voltage- replace the fuse and check for short in tail lights or stop lights.
Note:The dash lights get power from the STOP TAIL light circuit.
Check for intermittent short on the dark green wire that’s connected to the temp switch. If this wire is contacting ground (body metal) the temp light will go on.
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