Circuit Description
The RF damper actuator is controlled by the Electronic Suspension Control Module with a Pulse-Width Modulation (PWM) signal. Battery voltage is modulated (switched on and off) at a high frequency (2.0 kHz), thus controlling the amount of current delivered to the actuator. By controlling the amount of current to the actuator the Electronic Suspension Control Module can then control the damping force in the damper. A higher level of damping force is achieved by providing correspondingly higher current levels, relating to higher percentages of PWM duty cycle.
The default damper state (no battery voltage) is one that provides a minimum damping force.
Conditions for Running the DTC
| • | The ignition is on. |
| • | The fault is detected during three consecutive ignition cycles, or during the same ignition cycle after clearing the DTC with the scan tool. |
Conditions for Setting the DTC
The DTC is set when the Electronic Suspension Control Module measures a feedback voltage lower than a threshold value during two consecutive damper diagnostic test procedures. The threshold voltage required to set the DTC varies based upon battery voltage and the PWM signal.
Action Taken When the DTC Sets
| • | The SERVICE RIDE CONTROL message will be displayed. |
| • | ALL the damper actuators will be disabled by commanding 0 percent PWM duty cycle (ground switch open). |
| • | The damper relay control switch will be opened and the damper relay de-energized. |
| • | The vehicle speed will be limited. |
| • | The vehicle ride will be soft. |
Conditions for Clearing the MIL/DTC
| • | The scan tool can be used to clear the DTC. |
| • | The On-Board diagnostic CLEAR RSS CODES feature can be used to clear the DTC. |
| • | The DTC is saved as history when the Electronic Suspension Control Module no longer sees a short to ground on the damper low-side drive circuit. The DTC will clear if the fault does after 50 consecutive ignition cycles. |
Diagnostic Aids
Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
Test Description
The number(s) below refer to the step number(s) on the diagnostic table.
-
Tests for voltage at the coil side of the RF strut actuator.
-
Verifies that the Electronic Suspension Control Module is providing ground to the RF strut actuator.
-
Tests if ground is constantly being applied to the RF strut actuator.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Road Sensing Suspension Diagnostic System Check? | -- | Go to Step 2 | Go to Diagnostic System Check |
2 |
Does the RF strut actuator turn ON and OFF with each command? | -- | Go to Diagnostic Aids | Go to Step 3 |
Does the test lamp illuminate? | -- | Go to Step 4 | Go to Step 10 | |
Does the test lamp turn ON and OFF with each command? | -- | Go to Step 8 | Go to Step 5 | |
Does the test lamp remain illuminated with each command? | -- | Go to Step 7 | Go to Step 6 | |
6 | Test the ground circuit of the RF strut actuator for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 9 |
7 | Test the ground circuit of the RF strut actuator for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 9 |
8 | Inspect for poor connections at the RF strut actuator. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 11 |
9 | Inspect for poor connections at the harness connector of the Electronic Suspension Control Module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 12 |
10 | Repair the damper control circuit of the RF strut actuator. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 13 | -- |
11 | Replace the RF strut. Refer to Strut Assembly Replacement in Front Suspension. Did you complete the replacement? | -- | Go to Step 13 | -- |
12 |
Important: Perform the set up and calibration procedure for the Electronic Suspension Control Module. Replace the Electronic Suspension Control Module. Refer to Electronic Suspension Control Module Replacement . Did you complete the replacement? | -- | Go to Step 13 | -- |
13 |
Does the DTC reset? | -- | Go to Step 2 | System OK |
