HVAC DTC Troubleshooting: 10 | 2012-2016 CR-V RM1/RM4,RE5/RE6 HONDA CR-V Service Manual

1.

Problem verification:

Problem verification

?1.	Turn the vehicle to the OFF (LOCK) mode and then the ON mode.

?2.	Do the Self-Diagnostic Function with the HVAC control unit.

?3.	Check for DTCs.

Is DTC 10 indicated?


	YES

Go to step 2.


	NO

Intermittent failure. Check for loose wires or poor connections on the blower motor circuit.?

2.

Fuse check:

Fuse check

?1.	Turn the vehicle to the OFF (LOCK) mode.

?2.

Check the following fuse.

Fuse	No. A2-8 (40 A)
Location	Under-hood fuse/relay box

Is the fuse OK?


	YES

Go to step 3.


	NO

Replace the fuse, and recheck. If fuse blows again, repair a short in the No. A2-8 (40 A) fuse circuit.?

3.

Blower motor power circuit check:

Blower motor power circuit check

?1.

Disconnect the following connector.

Blower motor 2P connector

?2.	Turn the vehicle to the ON mode.

?3.

Measure the voltage between test points 1 and 2.

Test condition	Vehicle ON mode
Test condition	Blower motor 2P connector: disconnected
Test point 1	Blower motor 2P connector No. 2
Test point 2	Body ground

Is there battery voltage?


	YES

Go to step 4.


	NO

Go to step 12.

4.

Blower motor operation check:

Blower motor operation check

?1.	Turn the vehicle to the OFF (LOCK) mode.

?2.	Reconnect the blower motor 2P connector.

?3.

Connect terminals A and B with a jumper wire.

Terminal A	Blower motor 2P connector No. 1
Terminal B	Body ground

?4.	Turn the vehicle to the ON mode.

Does the blower motor run at high speed?


	YES

Go to step 5.


	NO

Replace the blower motor.?

5.

Open wire check (GND line):

Open wire check (GND line)

?1.	Turn the vehicle to the OFF (LOCK) mode.

?2.	Disconnect the jumper wire.

?3.

Disconnect the following connector.

Power transistor 4P connector

?4.

Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
Test condition	Power transistor 4P connector: disconnected
Test point 1	Power transistor 4P connector No. 3
Test point 2	Body ground

Is there continuity?


	YES

The GND wire is OK. Go to step 6.


	NO

Check for an open in the wire between the power transistor and body ground. If the wire is OK, check for poor ground at G402.?

6.

Open wire check (BLW-M line):

Open wire check (BLW-M line)

?1.

Connect terminals A and B with a jumper wire.

Terminal A	Power transistor 4P connector No. 3
Terminal B	Power transistor 4P connector No. 4

?2.	Turn the vehicle to the ON mode.

Does the blower motor run at high speed?


	YES

The BLW-M wire is OK. Go to step 7.


	NO

Repair an open in the wire between the power transistor and the blower motor.?

7.

Shorted wire check (BLOWER V/BLW-V line):

Shorted wire check (BLOWER V/BLW-V line)

?1.	Turn the vehicle to the OFF (LOCK) mode.

?2.	Disconnect the jumper wire.

?3.

Disconnect the following connector.

HVAC control unit 32P connector

?4.

Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	HVAC control unit 32P connector: disconnected
	Power transistor 4P connector: disconnected
Test point 1	HVAC control unit 32P connector No. 10
Test point 2	Body ground

Is there continuity?


	YES

Repair a short to ground in the wire between the HVAC control unit and the power transistor.?


	NO

The BLOWER V/BLW-V wire is not shorted. Go to step 8.

8.

Shorted wire check (BLOWER G/BLW-G line):

Shorted wire check (BLOWER G/BLW-G line)

?1.

Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	HVAC control unit 32P connector: disconnected
	Power transistor 4P connector: disconnected
Test point 1	HVAC control unit 32P connector No. 9
Test point 2	Body ground

Is there continuity?


	YES

Repair a short to ground in the wire between the HVAC control unit and the power transistor.?


	NO

The BLOWER G/BLW-G wire is not shorted. Go to step 9.

9.

Open wire check (BLOWER V/BLW-V line):

Open wire check (BLOWER V/BLW-V line)

?1.

Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	HVAC control unit 32P connector: disconnected
	Power transistor 4P connector: disconnected
Test point 1	HVAC control unit 32P connector No. 10
Test point 2	Power transistor 4P connector No. 2

Is there continuity?


	YES

The BLOWER V/BLW-V wire is OK. Go to step 10.


	NO

Repair an open in the wire between the HVAC control unit and the power transistor.?

10.

Open wire check (BLOWER G/BLW-G line):

Open wire check (BLOWER G/BLW-G line)

?1.

Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	HVAC control unit 32P connector: disconnected
	Power transistor 4P connector: disconnected
Test point 1	HVAC control unit 32P connector No. 9
Test point 2	Power transistor 4P connector No. 1

Is there continuity?


	YES

The BLOWER G/BLW-G wire is OK. Go to step 11.


	NO

Repair an open in the wire between the HVAC control unit and the power transistor.?

11.

Power transistor check:

Power transistor check

?1.	Test the power transistor.

Is the power transistor OK?


	YES

Replace the HVAC control unit.?


	NO

Replace the power transistor.?

NOTE: If the power transistor is faulty, check the blower motor for damage. If necessary, replace the blower motor.

12.

Blower motor relay check:

Blower motor relay check

?1.	Turn the vehicle to the OFF (LOCK) mode.

?2.	Remove the blower motor relay from the under-hood fuse/relay box, and test it.

Is the relay OK?


	YES

Go to step 13.


	NO

Replace the blower motor relay.?

13.

Open wire check (+B HTR MTR line):

Open wire check (+B HTR MTR line)

?1.

Measure the voltage between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	Blower motor 2P connector: disconnected
	Blower motor relay: disconnected
Test point 1	Blower motor relay 5P socket No. 1
Test point 2	Body ground

Is there battery voltage?


	YES

The +B HTR MTR wire is OK. Go to step 14.


	NO

An open in +B HTR MTR wire. Replace the under-hood fuse/relay box.?

14.

Open wire check (IG2 A/C line):

Open wire check (IG2 A/C line)

?1.	Turn the vehicle to the ON mode.

?2.

Measure the voltage between test points 1 and 2.

Test condition	Vehicle ON mode
	Blower motor 2P connector: disconnected
	Blower motor relay: disconnected
Test point 1	Blower motor relay 5P socket No. 3
Test point 2	Body ground

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 under-dash fuse/relay box and the blower motor relay in the under-hood fuse/relay box.?

15.

Open wire check (GND line):

Open wire check (GND line)

?1.	Turn the vehicle to the OFF (LOCK) mode.

?2.

Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	Blower motor 2P connector: disconnected
	Blower motor relay: disconnected
Test point 1	Blower motor relay 5P socket No. 5
Test point 2	Body ground

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 G402.?