1. Problem verification 1:
Turn the vehicle to the OFF (LOCK) mode, and the heater fan switch ON.
Does the blower motor stop?
YES
The failure is not duplicated, go to step 2.
NO
The failure is duplicated, go to step 16.
2. Problem verification 2:
Turn the vehicle to the ON mode, and the heater fan switch OFF.
Does the blower motor stop?
YES
The failure is not duplicated, go to step 3.
NO
The failure is duplicated, go to step 17.
3. Problem verification 3:
Operate the heater fan switch to each position, check the blower motor run in each speed.
Does the blower motor run in each speed?
YES
Intermittent failure, the system is OK at this time.
NO: Does not run at any speed
Failure is duplicated at all the speeds, go to step 7.
NO: Does not run at some of the speeds
Failure is duplicated at some of the speeds, go to step 4.
4. Heater fan switch check:
Is the heater fan switch OK?
YES
Go to step 5.
NO
Replace the heater fan switch.
5. Blower resistor check:
Test the blower resistor.
Is the blower resistor OK?
YES
Go to step 6.
NO
Replace the blower resistor.
6. Open wire check (BLOWER LOW line, BLOWER MID1 line, BLOWER MID2 line):
Is there battery voltage on the each terminal?
YES
Repair an open in the wire between the blower motor 2P connector No. 1 and the heater fan switch 8P connector terminal No. 2.
NO
Repair an open in the wire between the blower resistor and the heater fan switch.
7. Fuse check:
Is the fuse OK?
YES
Go to step 8.
NO
Replace the fuse, and recheck. If the fuse blows again, repair a short in the No. D2-4 (40 A) fuse circuit.
8. Blower motor power circuit check (HTR RLY OUT/BLOWER MTR line):
Blower motor 2P connector
Is there battery voltage?
YES
Go to step 9.
NO
Go to step 12.
9. Blower motor operation check (BLOWER MTR(HI)/BLOWER HI line):
Does the blower motor run?
YES
Go to step 10.
NO
Replace the blower motor.
10. Open wire check (BLOWER MTR(HI)/BLOWER HI line):
Blower resistor 4P connector
Is there battery voltage?
YES
The BLOWER MTR(HI)/BLOWER HI wire is OK. Go to step 11.
NO
Repair an open in the wire between the blower motor and the blower resistor.
11. Heater fan switch check:
Is the heater fan switch OK?
YES
Check for an open in the wire between the heater fan switch and body ground. If the wire is OK, check for poor ground at G403.
NO
Replace the heater fan switch.
12. Blower motor relay check:
Is the relay OK?
YES
Go to step 13.
NO
Replace the blower motor relay.
13. Open wire check (+B HTR MTR line):
Is there battery voltage?
YES
The +B HTR MTR wire is OK. Go to step 14.
NO
Repair an open in the wire between the No. D2-4 (40 A) fuse in the auxiliary under-dash fuse box A and the blower motor relay. If the wire is OK, replace the auxiliary under-dash fuse box A.
14. Open wire check (IG2 A/C line):
Is there battery voltage?
YES
The IG2 A/C wire is OK. Go to step 15.
NO
Repair an open in the wire between the No. C24 (7.5 A) fuse in the under-dash fuse/relay box and the blower motor relay. If the wire is OK, replace the under-dash fuse/relay box.
15. Open wire check (GND line):
Is there continuity?
YES
Repair an open in the wire between the blower motor relay and the blower motor.
NO
Check for an open in the wire between the blower motor relay and body ground. If the wire is OK, check for poor ground at G401.
16. Blower motor relay check:
Is the relay OK?
YES
Repair a short to power in the wire between the blower motor relay and the blower motor.
NO
Replace the blower motor relay.
17. Heater fan switch check:
Is the heater fan switch OK?
YES
Go to step 18.
NO
Replace the heater fan switch.
18. Shorted wire check (BLOWER LOW line, BLOWER MID1 line, BLOWER MID2 line):
Blower resistor 4P connector
Is there continuity?
YES
Repair a short to body ground in the wire(s) between the blower resistor and the heater fan switch.
NO
Repair a short to body ground in the wire between the blower motor 2P connector terminal No. 1 and the heater fan switch 8P connector terminal No. 2.