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Home >> Suzuki >> 2013 >> Kizashi Base, Automatic CVT Trans >> Repair and Diagnosis >> Heating, Ventilation & A/C (HVAC) >> HVAC Control Systems >> Air Conditioning System >> Diagnostic Information and Procedures >> DTC B1550-H/B1550-L: Lost Communication between HVAC Control Module and Auto A/C Panel >> DTC Troubleshooting
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DTC Troubleshooting

DTC TROUBLESHOOTING CHART

Step Action YES NO
1  DTC CHECK 
  1. Push engine switch to change ignition mode to "ON".
  2. Push engine switch to change ignition mode to "OFF".
  3. Push engine switch to change ignition mode to "ON" and check DTC.

Is DTC B1550-H or B1550-L still detected? 		 Go to Step 2. Intermittent trouble.
2  Communication circuit check 
  1. Disconnect "G20" and auto A/C panel connectors.
  2. Check the following points.
    • Resistance of "RED/GRN" wire circuit: less than 1 Ω
    • Resistance of "RED/GRN" wire circuit between auto A/C panel and ground: infinity

Are they in good condition? 		 Replace HVAC control module and recheck DTC, see HVAC CONTROL MODULE REMOVAL AND INSTALLATION . Repair or replace defective wire harness.
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