Component Tests and General Diagnostics

1. Disconnect water temperature indicator sender unit.
2. Connect one lead of Rotunda gauge system tester 021-00055, or equivalent, to water temperature indicator sender unit connector BK/O wire terminal, and other lead to ground.
3. Set tester to 74 ohms.
4. Turn ignition key to ON position and wait one minute.
5. Gauge should read "C".
6. Set tester to 9.7 ohms.
7. Wait one minute. Gauge should read "H".
8. If gauge does not operate according to specifications, replace. If gauge functions properly, refer to pinpoint test. [1][2]Component Tests and General Diagnostics