Air Conditioning/Climate Control Inoperative
- With Automatic Climate Control (ACC) set to LO, enter ISAT command Code 550. If A/C relay is operating, go to next step. If A/C relay is not operating, check Black wire between ETS ECU terminal No. 38 and relay terminal No. 85. Also check Yellow wire between ETS ECU terminal No. 37 and pressure switch on receiver for an open circuit or short to ground. If all wiring is okay, go to next step.
- With all components connected, A/C switched on, and engine running, check voltage signal at ETS ECU terminals No. 37 (Yellow wire) and No. 38 (Black wire). See A/C VOLTAGE SIGNAL SPECIFICATIONS table.
A/C VOLTAGE SIGNAL SPECIFICATIONS
| ETS ECU Terminal No. (Wire Color) |
Specification |
| 37 (Yellow Wire) |
| A/C On |
10-12 Volts |
| A/C Off |
Zero Volts |
| 38 (Black Wire) |
| A/C Relay Energized |
About 1 Volt |
| A/C Relay De-Energized |
10-12 Volts |
| A/C Relay DeEnergized |
Zero Volts |