Diagnostic Aids
When engine is allowed to cool to ambient temperature or overnight, CTS and IAT sensor resistance or temperature may be checked with a scan tester. Resistance readings of components should be close to each other.
Code 23 is set if signal wire or sensor ground is open. If Code 23 is intermittent, see TESTS W/O CODES article in this section.
INTAKE AIR TEMPERATURE SENSOR RESISTANCE
| Temperature: °F (°C) | Resistance: Ohms |
|---|---|
| 210 (100) | 185 |
| 160 (70) | 450 |
| 100 (38) | 1800 |
| 70 (20) | 3400 |
| 40 (4) | 7500 |
| 20 (-7) | 13,500 |
| 0 (-18) | 25,000 |
| -40 (-40) | 100,700 |