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Home >> Suzuki >> 2006 >> Grand Vitara Premium, RWD, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 68 (Air Conditioning System) >> Diagnostic Information and Procedures >> DTC B1504: Sunload Sensor and/or Its Circuit Malfunction >> DTC Troubleshooting
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DTC Troubleshooting

WARNING: This page is about a different car, the 2008 Suzuki Grand Vitara. However, it is still accessible from the selected car via links, so may be relevant.
DTC TROUBLESHOOTING CHART

Step Action YES NO
1  Sunload sensor power supply circuit check 
  1. Disconnect sunload sensor connector with ignition switch turned OFF.
  2. Check for proper connection to sunload sensor at "PNK" and "YEL" wire terminals.
  3. If OK, measure voltage between "PNK" wire terminal of sunload sensor connector and vehicle body ground with ignition switch turned ON.

Is voltage 4 - 6 V? 		 Go to Step 5. Go to Step 2.
2  Sunload sensor power supply circuit check 
  1. Disconnect connector from HVAC control module with ignition switch turned OFF.
  2. Check for proper connection to HVAC control module connector at "G52-12" and "G52-18" terminals.
  3. If OK, measure resistance between "PNK" wire terminal of sunload sensor connector and "G52-12" terminal of HVAC control module connector.

Is resistance below 5 Ω? 		 Go to Step 3. "PNK" wire open or high resistance circuit.
3  Sunload sensor power supply circuit check 
  1. Measure resistance between "PNK" wire terminal of sunload sensor connector and vehicle body ground.

Is resistance infinity? 		 Go to Step 4. "PNK" wire shorted to ground circuit.
4  Sunload sensor power supply circuit check 
  1. Measure voltage between "PNK" wire terminal of sunload sensor connector and vehicle body ground with ignition switch turned ON.

Is voltage 0 V? 		 Go to Step 5. "PNK" wire shorted to other circuit.
5  Sunload sensor signal circuit check 
  1. Disconnect HVAC control module connector with ignition switch turned OFF.
  2. Measure resistance between "YEL" wire terminal of sunload sensor connector and vehicle body ground.

Is resistance infinity? 		 Go to Step 6. "YEL" wire shorted to ground circuit.
6  Sunload sensor signal circuit check 
  1. Measure resistance between "G52-12" terminal of HVAC control module connector and "YEL" wire terminal of sunload sensor connector.

Is resistance below 5 Ω? 		 Go to Step 7. "YEL" wire open or high resistance circuit.
7  Sunload sensor signal circuit check 
  1. Measure voltage between "YEL" wire terminal of sunload sensor connector and vehicle body ground with ignition switch turned ON.

Is voltage 0 V? 		 Go to Step 8. "YEL" wire shorted to other circuit.
8  Sunload sensor check 
  1. Check sunload sensor referring to SUNLOAD SENSOR INSPECTION .

Is it in good condition? 		 HVAC control module faulty. Sunload sensor faulty.
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