DTC Troubleshooting
WARNING: This page is about a different car, the 2011 Suzuki SX4. However, it is still accessible from the selected car via links, so may be relevant.
B1504: SYMPTOM TROUBLESHOOTING REFERENCE CHART
| Step |
Action |
YES |
NO |
| 1 |
Was "Air Conditioning System Check" performed? |
Go to Step 2. |
Go to 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 Ω
- 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? |
Go to Step 3. |
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? |
Go to Step 4. |
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? |
Substitute a known-good HVAC control module and recheck. |
Replace sunload sensor. |