Diagnostic Test

CHARGING SYSTEM DTCS PRESENT
1. Turn the ignition on.
2. With the scan tool, read DTCs in the Powertrain Control Module (PCM).
  Are there any Charging System or related voltage DTCs present?
  
  Yes
  - Perform the appropriate Charging System DTC diagnostic procedures before continuing with this test. Refer to DTC INDEX .
  No
  - Go To 2
CHECK FOR AN ACTIVE DTC
NOTE:
This DTC must be active for the results of this test to be valid.
1. Turn the ignition on.
2. With the scan tool, read EPS DTCs and record on the vehicle repair order.
3. With the scan tool, erase EPS DTCs.
4. Start the vehicle.
5. Turn the steering wheel from stop to stop several times.
6. With the scan tool, read EPS DTCs.
  Did the DTC return?
  
  Yes
  - Go To 3
  No
  - Perform the TESTING FOR AN INTERMITTENT CONDITION procedure. Refer to TESTING FOR AN INTERMITTENT CONDITION .
BATTERY
NOTE:
Make sure the Battery is in good condition. Using the Midtronics Battery Tester or an equivalent Battery tester, test the Battery before continuing.

Does the Battery pass the load test for this specific application?

Yes
- Go To 4
No
- Replace the Battery in accordance with the Service Information.
- Perform the EPS VERIFICATION TEST. Refer to EPS VERIFICATION TEST .
CHECK THE FUSE
1. Turn the ignition on.
2. Using a 12-volt test light connected to ground, check the fuse for power.
  Is the fuse good?
  
  Yes
  - Go To 5
  No
  - If the related fuse is open, check the EPS Module power circuit for a short to ground.
  - Perform the EPS VERIFICATION TEST. Refer to EPS VERIFICATION TEST .
CHECK EPS MODULE HARNESS CONNECTOR/TERMINAL FOR DAMAGE
NOTE:
Check all terminals for broken, bent, pushed out, or corroded terminals.
1. Turn the ignition off.
2. Inspect the EPS Module wiring harness and electrical connectors.
  Were any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the ABS VERIFICATION TEST. Refer to ABS VERIFICATION TEST .
  No
  - Go To 6
(A901) FUSED (B+) CIRCUITS FOR AN OPEN OR HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the EPS Module C1 harness connector.
3. Disconnect the Body Control Module (BCM) C3 harness connector.
4. Turn the ignition on.
  NOTE:
  The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.
5. With a 12-volt test light connected to ground check the (A901) Fused (B+) circuit in the EPS Module C1 harness connector.
6. With a 12-volt test light connected to ground check the (A901) Fused (B+) circuit in the BCM C3 harness connector.
  Does the test light illuminate brightly?
  
  Yes
  - Go To 7
  No
  - Repair the (A901) Fused (B+) circuit(s) for an open or high resistance.
  - Perform the EPS VERIFICATION TEST. Refer to EPS VERIFICATION TEST .
(Z115) GROUND CIRCUIT FOR AN OPEN OR HIGH RESISTANCE
1. Turn the ignition off.
2. With a 12-volt test light connected to (B+) check the (Z115) Ground circuit in the EPS harness connector.
  Does the test light illuminate brightly?
  
  Yes
  - Go To 8
  No
  - Repair the (Z115) Ground circuit for an open or high resistance.
  - Perform the EPS VERIFICATION TEST. Refer to EPS VERIFICATION TEST .
CHECK RELATED HARNESS CONNECTIONS
1. Disconnect the EPS Module harness connectors.
2. Disconnect all related in-line harness connections (if equipped).
3. Disconnect the related component harness connectors.
4. Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
  - Proper connector installation.
  - Damaged connector locks.
  - Corrosion.
  - Other signs of water intrusion.
  - Weather seal damage (if equipped).
  - Bent terminals.
  - Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
  - Terminals that have been pushed back into the connector cavity.
  - Perform a terminal drag test on each connector terminal to verify proper terminal tension.
  Repair any conditions that are found.
5. Connect the EPS Module harness connectors. Be certain that the harness connectors are fully seated and the connector locks are fully engaged.
6. Connect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
7. Connect the related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
8. With the scan tool, erase DTCs.
9. Using the recorded Event and Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
10. With the scan tool, read EPS Module DTCs.
  Did the DTC return?
  
  Yes
  - Replace the Electric Power Steering (EPS) Module in accordance with Service Information. Refer to COLUMN, REMOVAL AND INSTALLATION .
  - Perform the EPS VERIFICATION TEST. Refer to EPS VERIFICATION TEST .
  No
  - Perform the EPS VERIFICATION TEST. Refer to EPS VERIFICATION TEST .
  - Test complete.