Test 5: ASCD Pump Circuit Check
- Check ASCD Pump
Turn ignition switch to LOCK position. Disconnect ASCD pump harness connector. Measure resistance between specified ASCD pump terminals (pump side). See ASCD PUMP RESISTANCE table. See Fig 1 . If resistance is as specified, go to next step. If resistance is not as specified, replace ASCD pump. - Harness Check
Ensure ignition switch is in LOCK position. Disconnect ASCD pump harness connector. Disconnect ASCD control unit harness connector. Check each circuit for an open or short between ASCD pump and ASCD control unit. See WIRING DIAGRAMS . Repair as necessary. - Inspect ASCD Pump Voltage Supply
Turn ignition switch to LOCK position. Raise and support vehicle. Access ASCD control unit harness connector. Start vehicle and place shift selector in Drive position. Increase vehicle speed to greater than 25 MPH. Ensure MAIN switch and SET/COAST indicator lights are illuminated. Backprobing ASCD connector, measure voltage between ground and terminal No. 12 (Blue/White wire). See Figure . If battery voltage exists, power supply is okay. If battery voltage does not exist, replace ASCD control unit.
ASCD PUMP RESISTANCE
| Check Resistance Between Terminals No. | Approximate Ohms |
|---|---|
| 1 & 2 | 65 |
| 1 & 3 | 65 |
| 1 & 4 | 3 |