Fault Code 24
Fault Code 24Differential Potentiometer
Test the 5 volt supply to differential potentiometer between pin 1 and pin 2 (ground) at the potentiometer connector. If there is no 5 V supply, inspect the harness for open circuit or short circuit to ground. If no harness faults are apparent, renew the Air Conditioning Control Module (A/CCM).
NOTE: The A/CCM provides a common 5 V output and ground to all servos, i.e. all servo potentiometers are fed by a 5 V rail. If all servos are inoperable check the A/CCM outputs and harness, renew the A/CCM.
Check resistance between pins 1 and 2, value should be 10 K Ohms ± 10% at 20 °C.
If the resistance measured falls outside the said limits, renew the potentiometer.
Check resistance between pins 1 and 3 at both maximum and minimum differential potentiometer positions; adjusted via the variable differential control thumb wheel situated between dash center face level vents.
Differential potentiometer position Resistance
Minimum differential (Red) approx. 8 K Ohms ± 10%
Maximum differential (Blue) approx. 2 K Ohms ± 10%
If the resistance measured falls outside the said limits, renew the potentiometer.