Diagnostic Test

TEST FOR INTERMITTENT CONDITION
1. Turn the ignition on.
2. With the scan tool, record and erase DTCs.
3. Cycle the ignition from on to off 3 times.
4. Turn the ignition on.
5. With the scan tool, read active PSM DTCs.
  Does the scan tool display this DTC as active?
  
  Yes
  - Go to step 2
  No
  - The condition that caused this symptom is currently not present. Check for an intermittent condition by inspecting the related wiring harness for chafed, pierced, pinched, and partially broken wires. Also, inspect the related connectors for broken, bent, pushed out, spread, corroded, or contaminated terminals. Repair as necessary.
  - Perform the BODY VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Body Control (BCM) - Standard Procedure .
MEASURE VOLTAGE AT PSM
1. Gain access to the Programmable Special Module (PSM) C2 harness connector, but do not disconnect.
2. Backprobe and measure the voltage on both the CAN B Bus (+) and the CAN B (-) circuits.
  Does the voltage read approximately 4.65 - 4.98 volts on the CAN B Bus (-) and 0.39 - 0.46 volts on the CAN B (+) circuits?
  
  Yes
  - Go to step 3
  No - Voltage Between 0.3 - 0.7 Volts on Both Circuits
  - Go to step 9
  No - Voltage Reads 0 Volts on Either Circuit
  - Go to step 7
  No - Voltage Above 10 Volts on Either Circuit
  - Go to step 5
CAN B BUS (+) CIRCUIT OPEN
1. Turn the ignition on.
2. With the scan tool select ECU View.
3. Using a fused jumper wire, connect one end to ground and with the other end backprobe the CAN B Bus (+) circuit at the PSM C2 harness connector.
  NOTE: A red "X" will appear next to modules that can no longer communicate on the Bus.
  
  Did a red "X" appear next to any modules on the scan tool?
  
  Yes
  - Using the SYSTEM WIRING DIAGRAMS to further isolate the open in the circuit, repair the CAN B Bus (+) circuit for an open.
  - Perform the BODY VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Body Control (BCM) - Standard Procedure .
  No
  - Go to step 4
CAN B BUS (-) CIRCUIT OPEN
1. With the scan tool select ECU View.
2. Using a fused jumper wire, connect one end to ground and with the other end backprobe the CAN B Bus (-) circuit at the PSM C2 harness connector.
  NOTE: A red "X" will appear next to modules that can no longer communicate on the Bus.
  
  Did a red "X" appear next to any modules on the scan tool?
  
  Yes
  - Using the SYSTEM WIRING DIAGRAMS to further isolate the open in the circuit, repair the CAN B Bus (-) circuit for an open.
  - Perform the BODY VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Body Control (BCM) - Standard Procedure .
  No
  - Inspect the wiring and connectors for damage. If OK, replace and program the Programmable Special (PSM) Module in accordance with the service information.
  - Perform the BODY VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Body Control (BCM) - Standard Procedure .
CAN B BUS (+) CIRCUIT FOR A SHORT TO VOLTAGE
1. Turn the ignition off.
2. Disconnect the PSM C2 harness connector.
3. Turn the ignition on.
4. Measure the voltage between the CAN B Bus (+) circuit and ground.
  Is the voltage above 10.0 volts?
  
  Yes
  - Disconnect each CAN B Bus module one at a time while observing the voltage to determine if the short is caused by an internal short within a module. Replace the module, in accordance with the service information, that when disconnected eliminates the short to voltage. If the short condition is still present with all CAN B Bus modules disconnected use the SYSTEM WIRING DIAGRAMS to help isolate and repair the CAN B Bus (+) circuit for a short to voltage.
  - Perform the BODY VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Body Control (BCM) - Standard Procedure .
  No
  - Go to step 6
CAN B BUS (-) CIRCUIT FOR A SHORT TO VOLTAGE
1. Measure the voltage between the CAN B Bus (-) circuit and ground.
  Is the voltage above 10.0 volts?
  
  Yes
  - Disconnect each CAN B Bus module one at a time while observing the voltage to determine if the short is caused by an internal short within a module. Replace the module, in accordance with the service information, that when disconnected eliminates the short to voltage. If the short condition is still present with all CAN B Bus modules disconnected use the SYSTEM WIRING DIAGRAMS to help isolate and repair the CAN B Bus (-) circuit for a short to voltage.
  - Perform the BODY VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Body Control (BCM) - Standard Procedure .
  No
  - Inspect the wiring and connectors for damage. If OK, replace and program the Programmable Special (PSM) Module in accordance with the service information.
  - Perform the BODY VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Body Control (BCM) - Standard Procedure .
CAN B BUS (+) CIRCUIT FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Measure the resistance between ground and the CAN B Bus (+) circuit.
  Is the resistance above 1000.0 Ohms?
  
  Yes
  - Go to step 8
  No
  - Disconnect each CAN B Bus module one at a time while observing the resistance to determine if the short is caused by an internal short within a module. Replace the module, in accordance with the service information, that when disconnected eliminates the short to ground. If the short condition is still present with all CAN B Bus modules disconnected use the SYSTEM WIRING DIAGRAMS to help isolate and repair the CAN B Bus (+) circuit for a short to ground.
  - Perform the BODY VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Body Control (BCM) - Standard Procedure .
CAN B BUS (-) CIRCUIT FOR A SHORT TO GROUND
1. Measure the resistance between ground and the CAN B Bus (-) circuit.
  Is the resistance above 1000.0 Ohms?
  
  Yes
  - Inspect the wiring and connectors for damage. If OK, replace and program the Programmable Special Module (PSM) in accordance with the service information.
  - Perform the BODY VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Body Control (BCM) - Standard Procedure .
  No
  - Disconnect each CAN B Bus module one at a time while observing the resistance to determine if the short is caused by an internal short within a module. Replace the module, in accordance with the service information, that when disconnected eliminates the short to ground. If the short condition is still present with all CAN B Bus modules disconnected use the SYSTEM WIRING DIAGRAMS to help isolate and repair the CAN B Bus (-) circuit for a short to ground.
  - Perform the BODY VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Body Control (BCM) - Standard Procedure .
CAN B BUS (+) CIRCUIT SHORTED TO THE (D54) CAN B BUS (-) CIRCUIT
1. Measure the resistance between the CAN B Bus (+) circuit and CAN B Bus (-) circuit.
  Is any resistance present?
  
  Yes
  - Disconnect each CAN B Bus module one at a time while observing the resistance to determine if the short is caused by an internal short within a module. Replace the module, in accordance with the service information, that when disconnected eliminates the short between the two circuits. If the short condition is still present with all CAN B Bus modules disconnected use the SYSTEM WIRING DIAGRAMS to help isolate and repair the CAN B Bus (+) circuit for a short to the CAN B Bus (-) circuit.
  - Perform the BODY VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Body Control (BCM) - Standard Procedure .
  No
  - Inspect the wiring and connectors for damage. If OK, replace and program the Programmable Special Module (PSM) in accordance with the service information.
  - Perform the BODY VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Body Control (BCM) - Standard Procedure .