Central Control Module (CCM)

Diagnostic Chart:

Wiring Diagram:

CIRCUIT DESCRIPTION

The CCM has the ability to detect faults in the power steering solenoid actuator output circuit. The Variable Effort Steering (VES) electrical system allows for an electrical controlled solenoid to restrict the amount of power steering fluid flowing through the power steering system. The CCM controls how much current flows through the VES circuits.

TEST CONDITIONS

This is a test that will take place whenever the VES system is operating. IGN 3 must be present for DTC 28 to set. Turning ignition "OFF" then "ON" again will reset DTC 28.

FAILURE CONDITIONS

This DTC will set when VES function (at low speeds) is "ON" and VES solenoid actuator feedback exceeds 260 ma or when VES function is "ON" (at high speeds) and VES solenoid actuator feedback is less than 360 ma.

ACTION TAKEN

DTC 28 will set. If the fault is a short to B+ a DTC 27 will also set.

TEST DESCRIPTION

Number(s) below refer to circled number(s) on the diagnostic chart.

1. This test checks for a shorted VES solenoid actuator, normal VES solenoid actuator, or too much resistance in VES circuits or VES solenoid actuator.

2. This test indicated if the VES solenoid actuator, or circuit is causing a high resistance condition.

DIAGNOSTIC AIDS

If the DTC is a history code, the problem may be intermittent. Try performing the test shown while "wiggling" wiring and connectors; this can often cause the fault to appear. Check for intermittent shorts to B+ in the wiring from the CCM to the power steering pump solenoid. If CKT 1294, CKT 1295, or the VES solenoid actuator is shorted to B+, shorted to ground or goes open, the CCM will completely disable the variable effort output.

A Tech 1 can be used to monitor VES solenoid actuator output.