No Response From EHPS (Electro-Hydraulic Power Steering)

NO RESPONSE FROM EHPS (ELECTRO-HYDRAULIC POWER STEERING) MODULE





For a complete wiring diagram, refer to the Wiring Information.






1. TEST FOR INTERMITTENT CONDITION

NOTE: Check for any TSB(s) related to the condition. If a TSB applies, perform the procedure outlined in the TSB before continuing.

1. Turn the ignition on.

NOTE: Make sure the battery voltage is between 10.0 and 16.0 volts.

2. With the scan tool, read the module status.

NOTE: Check the BCM for any active CAN hardware DTCs, perform DTC before proceeding.

Does the scan tool indicate that the module is active on the bus?

Yes

- The no response condition is 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 pin tension.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 2

2. CHECK THE (A951) FUSED B(+) CIRCUIT FOR AN OPEN OR SHORT
1. Turn the ignition off.
2. Disconnect the EHPS Module harness connector.
3. Using a 12-volt test light connected to ground, check the (A951) Fused B(+) circuit.

Does the test light illuminate brightly?

Yes

- Go To 3

No

- Repair the open or short in the (A951) Fused B(+) circuit.
- Perform the EHPS VERIFICATION TEST. EHPS Verification Test.

3. CHECK THE (F944) IGNITION SWITCH OUTPUT (RUN-START) CIRCUIT FOR AN OPEN OR SHORT
1. Turn the ignition off.
2. Disconnect the EHPS Module harness connector.
3. Using a 12-volt test light connected to ground, check the (F944) Ignition Switch Output (Run-Start) circuit.

Does the test light illuminate brightly?

Yes

- Go To 4

No

- Repair the open or short in the (F944) Ignition Switch Output (Run-Start) circuit.
- Perform the EHPS VERIFICATION TEST. EHPS Verification Test.

4. CHECK THE (Z906) GROUND CIRCUIT FOR AN OPEN
1. Using a 12-volt test light connected to 12-volts, check the (Z906) Ground circuit.

Does the test light illuminate brightly?

Yes

- Go To 5

No

- Repair the open in the (Z906) Ground circuit.
- Perform the EHPS VERIFICATION TEST. EHPS Verification Test.

5. CHECK THE (D65) AND (D64) CAN C BUS CIRCUITS FOR AN OPEN
1. Disconnect the Front CAN C Star Connector C9 harness connector.
2. Measure the resistance of the (D65) CAN C Bus (+) circuit between the Front CAN C Star Connector C9 harness connector and the EHPS Module harness connector.
3. Measure the resistance of the (D64) CAN C Bus (-) circuit between the Front CAN C Star Connector C9 harness connector and the EHPS Module harness connector.

Are the resistances below 5.0 Ohms?

Yes

- Replace and program the Electro-Hydraulic Power Steering (EHPS) Assembly. Power Steering Pump - Removal.
- Perform the EHPS VERIFICATION TEST. EHPS Verification Test.

No

- Repair the open in the (D65) CAN C Bus (+) or (D64) CAN C Bus (-) circuit.
- Perform the EHPS VERIFICATION TEST. EHPS Verification Test.