DTC 1
DTC 1: A Problem in the Rear Blower Motor Circuit1. Check the No. 55 (30 A) fuse in the under-hood fuse/relay box, and the No 3 (7.5 A) fuse in the driver's under-dash fuse/relay box.
Are the fuses OK?
YES - Go to step 2.
NO - Replace the fuse(s), and recheck.
2. Connect the No. 2 terminal of the rear blower motor 2P connector to body ground with a jumper wire.
3. Turn the ignition switch ON (II).
Does the rear blower motor run?
YES - Go to step 4.
NO - Go to step 25.
4. Turn the ignition switch OFF.
5. Disconnect the jumper wire.
6. Disconnect the rear power transistor 4P connector.
7. Check for continuity between the No. 3 terminal of the rear power transistor 4P connector and body ground.
Is there continuity?
YES - Go to step 8.
NO - Check for an open in the wire between the rear power transistor and body ground. If the wire is OK, check for poor ground at G501.
8. Connect the No. 2 and No. 3 terminals of the rear power transistor 4P connector with a jumper wire.
9. Turn the ignition switch ON (II).
Does the rear blower motor run at high speed?
YES - Go to step 10.
NO - Repair open in the wire between the rear power transistor and the rear blower motor.
10. Turn the ignition switch OFF.
11. Disconnect the jumper wire.
12. Disconnect climate control unit connector A (20P)
13. Check for continuity between the No. 3 and No. 4 terminals of climate control unit connector A (20P) and body ground individually.
Is there continuity?
YES - Repair any short to body ground in the wire(s) between the climate control unit and the rear power transistor.
NO - Go to step 14.
14. Check for continuity between following terminals of climate control unit connector A (20P) and rear power transistor 4P connector.
20P: 4P:
No. 3 No. 4
No. 4 No. 1
Is there continuity?
YES - Go to step 15.
NO - Repair any open in the wire(s) between the climate control unit and the rear power transistor.
15. Reconnect climate control unit connector A (20P)
16. Test the rear power transistor.
Is the rear power transistor OK?
YES - Go to step 17.
NO - Replace the rear power transistor.
17. Disconnect the rear heater-A/C control switch 10P connector.
18. Test the rear heater-A/C control switch.
Is the rear heater-A/C control switch OK?
YES - Go to step 19.
NO - Replace the rear heater-A/C control switch.
19. Check for continuity between body ground and climate control unit connector A (20P) terminals No 6, 7, 8, 9, 10, and 20 individually.
Is there continuity?
YES - Repair any short to body ground in the wire(s) between the climate control unit and the rear heater-A/C control switch.
NO - Go to step 20.
20. Turn the ignition switch ON (II), and check the same terminals for voltage.
Is there any voltage?
YES - Repair any short to power in the wire(s) between the climate control unit and the rear heater A/C control switch This short may also damage the rear heater A/C control switch Repair the short to power before replacing the rear heater-A/C control switch.
NO - Go to step 21.
21. Turn the ignition switch OFF.
22. Check for continuity between the No. 7 terminal of the rear heater A/C control switch 10P connector and body ground.
Is there continuity?
YES - Go to step 23.
NO - Check for an open in the wire between the rear heater-A/C control switch and body ground. If the wire is OK, check for poor ground at G501.
23. Turn the ignition switch OFF.
24. Check for continuity between following terminals of climate control unit connector A (20P) and the rear heater-A/C control switch 10P connector.
20P: 10P:
No. 6 No. 6
No. 7 No. 5
No. 8 No. 4
No. 9 No. 3
No. 10 No. 2
No. 20 No. 1
Is there continuity?
YES - Check for loose wires or poor connections at climate control unit connector A (20P) and at the rear heater-A/C control switch 10P connector. If the connections are good, substitute a known-good climate control unit, and recheck. If the symptom/indication goes away, replace the original climate control unit.
NO - Repair any open in the wire(s) between the climate control unit and the rear heater-A/C control switch.
25. Disconnect the jumper wire.
26. Disconnect the rear blower motor 2P connector.
27. Measure the voltage between the No. 1 terminal of the rear blower motor 2P connector and body ground.
Is there battery voltage?
YES - Replace the rear blower motor.
NO - Go to step 28.
28. Turn the ignition switch OFF.
29. Remove the rear blower motor relay from the left side of rear heater A/C unit, and test it.
Is the relay OK?
YES - Go to step 30.
NO - Replace the rear blower motor relay.
30. Measure the voltage between the No. 1 terminal of the rear blower motor relay 4P connector and body ground.
Is there battery voltage?
YES - Go to step 31.
NO - Repair open in the wire between the No. 55 fuse in the under hood fuse/relay box and the rear blower motor relay.
31. Turn the ignition switch ON (II).
32. Measure the voltage between the No. 2 terminal of the rear blower motor relay 4P connector and body ground.
Is there battery voltage?
YES - Go to step 33.
NO - Repair open in the wire between the No. 3 fuse in the driver's under-dash fuse/relay box and the rear blower motor relay.
33. Turn the ignition switch OFF.
34. Check for continuity between the No. 4 terminal of the rear blower motor relay 4P connector and body ground.
Is there continuity?
YES - Repair open in the BLU/YEL wire between the rear blower motor relay and the rear blower motor.
NO - Check for an open in the wire between the rear blower motor relay and body ground. If the wire is OK, check for poor ground at G501.