Honda Accord: A/C Signal Circuit Troubleshooting
NOTE: • If the blower motor does not run at all speeds, the A/C compressor will be inoperative. Run the self-diagnostic function, and check for DTC B1241.
Before performing any other troubleshooting, repair the cause of the inoperative blower motor.
• Do not use this troubleshooting procedure if any of the following items are operative: The condenser fan, the radiator fan, or the A/C compressor, or if the heater is inoperative. Refer to the symptom troubleshooting index.
• Before doing symptom troubleshooting, check for powertrain DTCs (see page 11-3).
1. Turn the ignition switch to ON (II).
2. Check if the blower motor operates at all speeds.
YES
-Go to step 3.
NO
-Repair the problem in the blower motor circuit (see page21-166).
3. Do the sensor input display mode (see page 21-107).
Is Sensor #5 (evaporative outlet air temperature) above 3 В°C?.
YES
-Go to step 4.
NO
-Go to step 9.
4. Turn the ignition switch to LOCK (0).
5. Disconnect climate control unit connector A (28P).
6. Turn the ignition switch to ON (II).
7. Measure the voltage between climate control unit connector A (28P) terminal No. 21 and body ground.
CLIMATE CONTROL UNIT CONNECTOR A (28P)
Wire side of female terminals
* 1 : With navigation
*2: Without navigation
Is there battery voltage? YES-
Replace the climate control unit (with navigation) (see page 21-190), (without navigation) (see page 21-191 ).
NO
-Go to step 8.
8. Measure the voltage between driver's under-dash fuse/relay box connector F (33P) terminal No. 5 and body ground.
DRIVER'S UNDER-DASH FUSE/RELAY BOX CONNECTOR F (33P)
Wire side of female terminals
Is there battery voltage? YES
-Repair an open in the wire between the climate control unit and the MICU.
NO
-Check for loose wire or poor connections at driver's under-dash fuse/relay box connector F (33P) terminal Mo. 5. if the connections are good, substitute a known-good MICU and recheck. If the symptom goes away, replace the original MICU.
9. Turn the ignition switch to LOCK (0).
10. Disconnect climate control unit connector B (12P).
11. Measure the evaporator temperature sensor resistance between climate control unit connector A (28P) terminal No. 23 and connector B (12P) terminal No. 10.
CLIMATE CONTROL UNIT CONNECTOR A (28P)
Wire side of female terminals
CLIMATE CONTROL UNIT CONNECTOR B (12P)
Wire side of female terminals
* 1 : With navigation
*2: Without navigation
Is the resistance less than 24 kO? YES-
Check for loose wires or poor connections at the climate control unit connectors. If the connections are good, substitute a known-good climate control unit and recheck. If the symptom goes away, replace the original climate control unit (with navigation) (see page 21-190), (without navigation) (see page 21-19D.
NO
-Test the evaporator temperature sensor (see page 21-58).
A/C Pressure Switch Circuit
Troubleshooting
NOTE:
• if the blower motor does not run at all speeds, the A/C
compressor will be inoperative. Run the
self-diagnostic function, and check for DTC B1241.
Before performing any other troubl ...
In-car Temperature Sensor Test
NOTE: Before testing the sensor, check for HVAC DTCs
(see page 21-101).
1. Remove the in-car temperature sensor (see page
21-184).
2. Test the in-car temperature sensor while holding it in
fr ...
See also:
Crankshaft Main Bearing Replacement
Main Bearing Clearance Inspection
1. To check the main bearing-to-journal oil clearance,
remove the lower block and the bearing halves (see
page 7-14).
2. Clean each main journal and the bearing ...
To Use Maintenance MinderTM
• Displaying the Engine Oil Life
1. Turn the ignition switch to ON
.
2. Press the (Select/Reset) knob
repeatedly
until the engine oil life appears on the
information display.
The Maint ...
Air Mix Control Motor Test
NOTE: Before testing the motor, check for HVAC DTCs
(see page 21-9).
1. Disconnect the 7P connector from the air mix control
motor.
Incorrectly applying power and ground to the air mix
contro ...