Honda Accord: 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 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.
• Check the A/C high-side pressure.
• Before doing symptom troubleshooting, check for powertrain DTCs (see page 11-3). Also check for B-CAN codes (see page 22-109).
1. Turn the ignition switch to ON (II).
2. Check if the blower motor operates at all speeds.
Does the blower motor operate 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 3В°C? YES
-Go to step 4.
NO-
Go to step 15.
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. Turn the ignition switch to LOCK (0).
9. Disconnect the A/C pressure switch 2P connector.
10. Turn the ignition switch to ON (II).
11. Measure the voltage between A/C pressure switch 2P connector terminal No. 2 and body ground.
A /C PRESSURE SWITCH 2P CONNECTOR
Wire side of female terminals
Is there battery voltage? YES-
Go to step 12.
NO
-Repair an open in the wire between the A/C pressure switch and the MICU. If the wire is OK, substitute a known-good MICU and recheck. If the symptom goes away, replace the original MICU.
12. Check for continuity between terminals No. 1 and No. 2 of A/C pressure switch.
A/C PRESSURE SWITCH
Is there continuity? Y E S
- G o to step 13.
NO
-Replace the A/C pressure switch.
13. Connect A/C pressure switch 2P connector terminal No. 2 to body ground with a jumper wire.
A/C PRESSURE SWITCH 2P CONNECTOR
Wire side of female terminals
Do the compressor and fans operate? YES
-Go to step 14.
NO
-Check for B-CAN codes (see page 22-109).
14. Check for continuity between climate control unit connector A (28P) terminal No. 21 and A/C pressure switch 2P connector terminal No. 1.
CLIMATE CONTROL UNIT CONNECTOR A (28P)
Wire side of female terminals
A /C PRESSURE SWITCH 2P CONNECTOR
Wire side of female terminals
*1: With navigation
*2: Without navigation
Is there continuity? YES
-Check for loose wires or poor connections at the climate control unit connector A (28P) and at the A/C pressure switch 2P connector.
NO
-Repair an open in the wire between the HVAC control unit and A/C pressure switch.
15. Turn the ignition switch to LOCK (0).
16. Disconnect climate control unit connector A (28P) and B(12P).
17. Measure the evaporator temperature sensor resistance between climate control u n i t 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 21-191 ) . NO
-Test the evaporator temperature sensor (see page 21-58).
Climate Control Switch
Communication Line Circuit
Troubleshooting
1. Operate the climate control system with the
passenger's climate control switch in all modes.
Does the climate control system operate?
YES-lntermittent failure. Check for loose wires or
poor c ...
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 troubl ...
See also:
Floor Mats
The driver’s and right rear
passenger’s floor mats that came
with your vehicle hook over the floor
mat anchors. This keeps the floor
mats from sliding forward and
possibly interfering ...
APP Sensor Signal I n s p e c t i o n
NOTE:
- This procedure checks the APP sensor in its fully
closed position. In any other position, the APP sensor
stores DTCs which are covered in other
troubleshooting procedures.
- Check for P ...
Overview of Contents
Contents
A convenient reference to the
sections in this manual.
Your Vehicle at a Glance
A quick reference to the main
controls in your vehicle.
Driver and Passenger Safety
Important informat ...