Diagnostic Aids

Check for the following conditions if a history or intermittent DTC is indicated.

A poor connection at the SSPS control module. Inspect the harness connectors for backed out terminals, improper mating, improperly formed or damaged terminals, and poor terminal to wire connections.
A damaged wiring harness. Inspect the wiring harness for damages. If the wiring harness appears to be in good condition, observe the display on the DMM while moving the connectors and wiring harnesses related to the circuits. A change in the DMM display during the test will indicate the location of the fault.

DTC C1604 ECU (EEPROM ERROR) DIAGNOSTIC PROCEDURE

Step	Action	Value(s)	Yes	No
1	Did you perform the Variable Effort Steering Diagnostic System Check?	-	Go to Step 2.	Go to DIAGNOSTIC SYSTEM CHECK-VARIABLE EFFORT STEERING .
2	Install a scan tool. Turn ON the ignition, with the engine OFF. Use a scan tool in order to clear the DTCs. Operate the vehicle within Conditions for Running the DTC. Did the DTC fail this ignition?	-	Go to Step 3.	Go to Step 4.
3	Replace the SSPS control module. Did you complete the replacement?	-	Go to Step 4.	-
4	Operate the system in order to verify the repair. Did you correct the condition?	-	System OK	Go to Step 2.