LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Suzuki >> 2006 >> Grand Vitara Premium, RWD, Standard >> Repair and Diagnosis >> Heating, Ventilation & A/C (HVAC) >> HVAC Control Systems >> Air Conditioning System >> Diagnostic Information And Procedures >> DTC B1502: Inside Air Temperature Sensor And/Or Its Circuit Malfunction >> DTC Troubleshooting
April 5, 2026: LEMON Manuals is launched! Read the announcement.

DTC Troubleshooting

NOTE: When DTC B1503, B1511, B1512 and B1530 are indicated together, it is possible that "BLK/RED" wire circuit open.
DTC TROUBLESHOOTING CHART

Step Action YES NO
1  Inside air temperature sensor signal circuit check 
  1. Disconnect inside air temperature sensor connector with ignition switch turned OFF.
  2. Check for proper connection to inside air temperature sensor at "BLU/BLK" and "BLK/RED" wire terminals.
  3. If OK, measure voltage between "BLU/BLK" wire terminal of inside air temperature 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  Inside air temperature sensor signal 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 "G52-20" and "G52-13" terminals.
  3. If OK, measure resistance between "BLU/BLK" wire terminal of inside air temperature sensor connector and "G52-20" terminal of HVAC control module connector.

Is resistance below 5 Ω? 		 Go to Step 3. "BLU/BLK" wire open or high resistance circuit.
3  Inside air temperature sensor signal circuit check 
  1. Measure resistance between "BLU/BLK" wire terminal of inside air temperature sensor connector and vehicle body ground.

Is resistance infinity? 		 Go to Step 4. "BLU/BLK" wire shorted to ground circuit.
4  Inside air temperature sensor signal circuit check 
  1. Measure voltage between "BLU/BLK" wire terminal of inside air temperature sensor connector and vehicle body ground with ignition switch turned ON.

Is voltage 0 V? 		 Go to Step 5. "BLU/BLK" wire shorted to other circuit.
5  Inside air temperature sensor ground circuit check 
  1. Connect HVAC control module connector with ignition switch turned OFF.
  2. Measure resistance between "BLK/RED" wire terminal of inside air temperature sensor connector and vehicle body ground.

Is resistance below 5 Ω? 		 Go to Step 7. Go to Step 6.
6  Inside air temperature sensor ground circuit check 
  1. Measure resistance between "G52-13" terminal of HVAC control module connector and vehicle body ground.

Is resistance below 5 Ω? 		 "BLK/RED" wire open or high resistance circuit. HVAC control module faulty.
7  Inside air temperature sensor check 
  1. Check inside air temperature sensor referring to INSIDE AIR TEMPERATURE SENSOR INSPECTION .

Is it in good condition? 		 HVAC control module faulty. Inside air temperature sensor faulty.
scientia non olet · About LEMON Manuals