Diagnostic Test

CHECK THE MODULE STATUS ON THE CAN C BUS
1. Turn the ignition on.
2. With the scan tool, read the CAN topology on the Vehicle View screen.
  Does the Vehicle View screen indicate that the Module is active on the bus?
  
  Yes
  - The condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct terminal tension and repair as necessary. If no problems are found, test complete.
  - BODY VERIFICATION TEST .
  No
  - Go To 2
CHECK THE (A901) FUSED B(+) CIRCUIT FOR AN OPEN OR SHORT TO GROUND
NOTE:
The CAN bus will remain active with the scan tool connected and the ignition off.

NOTE:
Leave the scan tool connected

and on the Vehicle View screen.
1. Turn the ignition off.
2. Disconnect the Radio Frequency (RF) Hub Module C1 harness connector.
3. With a 12-volt test light connected to ground, check the (A901) Fused B(+) circuit at the RF Hub Module C1 harness connector.
  NOTE:
  The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.
  
  Does the test light illuminate brightly?
  
  Yes
  - Go To 3
  No
  - Repair the (A901) Fused B(+) circuit for an open or short to ground.
  - BODY VERIFICATION TEST .
CHECK THE (F941) FUSED IGNITION CIRCUIT FOR AN OPEN OR SHORT TO GROUND
1. Turn the ignition on.
2. With a 12-volt test light connected to ground, check the (F941) Fused Ignition circuit at the RF Hub Module C1 harness connector.
  Does the test light illuminate brightly?
  
  Yes
  - Go To 4
  No
  - Repair the (F941) Fused Ignition circuit for an open or short to ground.
  - BODY VERIFICATION TEST .
CHECK THE (Z906) GROUND CIRCUIT FOR AN OPEN OR HIGH RESISTANCE
1. With a 12-volt test light connected to 12 volts, check the (Z906) Ground circuit at the RF Hub Module C1 harness connector.
  Does the test light illuminate brightly?
  
  Yes
  - Go To 5
  No
  - Repair the (Z906) Ground circuit for an open or high resistance.
  - BODY VERIFICATION TEST .
CHECK THE (D1) CAN C1 BUS (+) CIRCUIT FOR AN OPEN OR HIGH RESISTANCE
1. Measure the voltage between ground and the (D1) CAN C1 Bus (+) circuit at the RF Hub Module C1 harness connector.
  Is the voltage below 2.5 volts?
  
  Yes
  - Repair the (D1) CAN C1 Bus (+) circuit for an open or high resistance.
  - BODY VERIFICATION TEST .
  No
  - Go To 6
CHECK THE (D2) CAN C1 BUS (-) CIRCUIT FOR AN OPEN OR HIGH RESISTANCE
1. Measure the voltage between ground and the (D2) CAN C1 Bus (-) circuit at the RF Hub Module C1 harness connector.
  Is the voltage below 1.3 volts?
  
  Yes
  - Repair the (D2) CAN C1 Bus (-) circuit for an open or high resistance.
  - BODY VERIFICATION TEST .
  No
  - Replace the Radio Frequency (RF) Hub Module in accordance with the Service Information. Refer to MODULE, RADIO FREQUENCY (RF HUB), REMOVAL AND INSTALLATION .
  - BODY VERIFICATION TEST .