B1504

DTC B1504: Sunload Sensor Circuit Malfunction

Wiring Diagram










DTC Detecting Condition and Trouble Area

NOTE:

When DTC B1502, B1503, B1511 and B1512 are indicated together, it is possible that sensor ground circuit is open.






DTC Troubleshooting

1.
Was "Air Conditioning System Check" performed?
YES -
Go to Step 2.
NO -
Go to Air Conditioning System Check Air Conditioning System Check:Auto A/C.

2. Wire harness check

Turn ignition switch to OFF position.
Disconnect connectors from sunload sensor and HVAC control module.
Check for proper connection to each signal circuit terminal and ground circuit terminal of sunload sensor and HVAC control module connectors.
If OK, check that sunload sensor circuit is as follows.
- Wiring harness resistance of each sunload sensor signal circuit and ground circuit is less than 3 ohms
- Insulation resistance of each sunload sensor signal circuit and ground circuit between sunload sensor connector and vehicle body ground is Infinity
- Circuit voltage of each sunload sensor signal circuit and ground circuit is 0 - 1 V with ignition switch turned ON

Are they in good condition?
YES -
Go to Step 3.
NO -
Sunload sensor power supply circuit and/or signal circuit are open, short or high resistance.

3. Sunload sensor power supply voltage check

Connect connector to HVAC control module with ignition switch turned OFF.
Turn ignition switch to ON position.
Measure voltage between signal terminal and ground terminal of sunload sensor connector.

Is voltage 4.5 - 5.5 V?
YES -
Go to Step 4.
NO -
Substitute a known-good HVAC control module and recheck.

4. Sunload sensor check

Check sunload sensor for performance referring to "Sunload Sensor Inspection".

Is it in good condition?
YES -
Substitute a known-good HVAC control module and recheck.
NO -
Replace sunload sensor.