DTC Troubleshooting

WARNING: This page is about a different car, the 2007 Suzuki Grand Vitara and 2006 Suzuki Grand Vitara. However, it is still accessible from the selected car via links, so may be relevant.

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 Disconnect inside air temperature sensor connector with ignition switch turned OFF. Check for proper connection to inside air temperature sensor at "BLU/BLK" and "BLK/RED" wire terminals. 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 Disconnect connector from HVAC control module with ignition switch turned OFF. Check for proper connection to HVAC control module connector at "G52-20" and "G52-13" terminals. 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 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 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 Connect HVAC control module connector with ignition switch turned OFF. 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 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 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.