Coolant Temperature Gauge Test
- Disconnect temperature gauge sending unit harness connector. Turn ignition on and observe temperature gauge. Gauge needle should indicate "C". Turn ignition off.
- Ground temperature gauge sending unit wire through a 3.4-watt test bulb. Turn ignition on. Test bulb should light and gauge needle should move to "H". If operation is not as specified, check temperature gauge resistance. See TEMPERATURE GAUGE RESISTANCE TEST table. See Figure, Figure or Figure
.
- If resistance is not as specified, replace temperature gauge. If resistance is okay, substitute known good temperature gauge sending unit, and recheck gauge operation.
TEMPERATURE GAUGE RESISTANCE TEST
| Terminals |
Ohms |
| ES300 & LS400 |
| "A"-"B" |
54 |
| "A"-"C" |
146 |
| "B"-"C" |
200 |
| SC300 & SC400 |
| "A"-"B" |
54 |
| "A"-"C" |
176 |
| "B"-"C" |
230 |