Sending Units (Resistance Check)
Most models have a combination temperature sending unit (a resistance sender and temperature switch). The smaller terminal is the resistance sender. Sending unit temperature values are stamped in the sender body.
Connect test resistor between sending unit wire and ground. Turn ignition on. Check gauge readings and compare to specifications in table. Remove sending unit and check resistance at position or temperature specified. If resistance is not to specifications, replace the sending unit.
TESTING COOLANT TEMP SENSOR RESISTANCE
| Part Number | Temperature °F (°C) | Resistance K-Ohms (X) |
|---|---|---|
| 0 280 130 023 | 68 (20) | 2.1-2.9 |
| 176 (80) | .27-.4 | |
| 0 280 130 026 | 68 (20) | 2.2-2.7 |
| 176 (80) | .3-.36 | |
TESTING COOLANT GAUGE RESISTANCE
| Model & Temperature °F (°C) | Resistance Ohms (X) | |
|---|---|---|
| 325 Series | ||
| 105 (40) | 287 | |
| 140 (60) | 132 | |
| 151 (66) | 112 | |
| 158 (70) | 96 | |
| 176 (80) | 68 | |
| 198 (92) | 49 | |
| 216 (102) | 36 | |
| 249 (115) | 25 | |
| 262 (128) | 18 | |
| 5, 6, & 7 Series | ||
| 105 (40) | 287 | |
| 142 (61) | 127 | |
| 249 (115) | 25 | |
| 262 (128) | 18 | |
TESTING FUEL GAUGE RESISTANCE
| Gauge Reading | Resistance Ohms (X) | Needle Position (° From Horizontal) | |
|---|---|---|---|
| 325 Series | |||
| R | 71.7 | 0° | |
| 1/4 | 55.2 | 11° | |
| 1/2 | 30.1 | 42° | |
| 3/4 | 12.7 | 69° | |
| F | 3.2 | 82° | |
| 5, 6, & 7 Series | |||
| R | 71.7 | 0° | |
| 1/4 | 59.2 | 19° | |
| 1/2 | 25.7 | 56° | |
| 3/4 | 13.0 | 70.5° | |
| F | 3.2 | 82.5° | |