Engine Coolant Temperature Gauge

Preliminary Setup
1. Disconnect the water temperature indicator sender unit connector. Connect one lead of the tester to the water temperature indicator sender unit connector, circuit 39 (R/W), and the other lead to ground.







Check C (Cold) Indication
2. Set the tester to 300 ohms. Key ON. Wait one minute. The engine coolant temperature gauge should indicate C (cold).







Check (Hot) Indication
3. Set the tester to 45 ohms. Wait one minute. The engine coolant temperature gauge should indicate one quarter to mid-range.
4. Set the tester to 18 ohms. Wait one minute. The engine coolant temperature gauge should indicate H (hot). Key OFF. Return to the pinpoint test.