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DTC Troubleshooting

WARNING: This page is about a different car, the 2008 Suzuki Grand Vitara and 2007 Suzuki Grand Vitara. However, it is still accessible from the selected car via links, so may be relevant.
DTC TROUBLESHOOTING TABLE

Step Action YES NO
1 DTC check of BCM
Is DTC U1144 (No. 1144) and DTC U1073 (No. 1073) detected together? 		 Go to DTC U1073 (NO. 1073): CONTROL MODULE COMMUNICATION BUS OFF . Go to Step 2.
2 DTC check of keyless start control module
  1. Check DTC for keyless start control module.

Is DTC No. 33 detected? 		 Go to DTC NO. 33: CONTROL MODULE COMMUNICATION BUS OFF . Go to Step 3.
3 Control module connector check
  1. Check connection of connectors of all control modules communicating by means of CAN.
  2. Recheck BCM for DTC.

Is DTC U1144 (No. 1144) detected? 		 Go to Step 4. Intermittent trouble. Check for intermittent by referring to INTERMITTENT AND POOR CONNECTION INSPECTION Intermittent and Poor Connection Inspection.
4 CAN communication circuit check
  1. Turn ignition switch to OFF position.
  2. Disconnect connectors from BCM and keyless start control module.
  3. Check CAN communication circuit between BCM and keyless start control module for open, short and high resistance.

Is each CAN communication circuit in good condition? 		 Go to Step 5. Repair circuit.
5 CAN communication circuit check
  1. Disconnect connectors of all control modules communicating by means of CAN.
  2. Check CAN communication circuit between control modules other than Step 4 for open, short and high resistance.

Is each CAN communication circuit in good condition? 		 Go to Step 6. Repair circuit.
6 Key indicator light operation check
  1. Connect connectors of disconnected control modules communicating by means of CAN.
  2. Push ignition knob switch of steering lock unit.

Does key indicator light turn ON? 		 Go to Step 7. Check keyless start control module power and ground circuit. If circuit is OK, substitute a known-good keyless start control module and recheck.
7 DTC check of BCM
  1. Disconnect connector from any one of control modules other than BCM.
  2. Recheck DTC for BCM.

Is DTC U1144 detected? 		 Disconnect connectors of control modules other than the one whose connector is disconnected in Step 1) one by one and check that DTC U1144 is detected by BCM each time connector is disconnected. When DTC U1144 is not detected by BCM while checking in this way, go to description under "NO" below. If DTC U1144 is detected by BCM even when connectors of all control modules that use CAN communication with BCM are disconnected, substitute a known-good BCM and recheck. Check power and ground circuit of control module disconnect in Step 1). If circuit is OK, substitute a known-good control module disconnected in Step 1) and recheck.
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