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For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 1999 🢒 Eldorado 🢒 Suspension 🢒 Road Sensing Suspension (RSS) 🢒 DTC C1768 Position Sensor Supply Fault

Object Number: 258350 Size: MF

Circuit Description

The CVRSS control module provides power (a regulated 8 volts) to each of the CVRSS position sensors. The control module also monitors this voltage supply for a fault condition which prevents proper regulation.

Conditions for Setting the DTC

The position sensor supply voltage is outside the valid range of 6 to 9 volts.

Action Taken When the DTC Sets
    • The DTC is set when the CVRSS enters the Speed Dependent damping mode.
    • The DTC is set when both of the ICCS2 Datalink Outputs are set to the default output states.
    • The DTC is set when the SERVICE RIDE CONTROL message is displayed.

The DTC turns HISTORY when the position sensor supply voltage returns to the valid range of 6 to 9 volts.

Conditions for Clearing the MIL/DTC
    • Use the scan tool.
    • Use the On-Board diagnostic CLEAR RSS CODES feature.

Test Description

Important: 

   • Do not backprobe the sensors, actuators, or any sealed connectors.
   • When all the diagnostics and repairs are complete, clear the DTCs and verify the operation.

The number(s) below refer to the step number(s) on the diagnostic table.

  1. Determines if the fault is due to a short circuit to ground condition.

    2.

  2. Determines if the fault is due to a short to voltage condition.

    3.

  3. Checks for a short circuit to ground condition in the LR position supply.

    4.

  4. Checks for a short circuit to ground condition in the RR position supply.

    5.

  5. Checks for a short circuit to ground condition in the LF position supply.

    6.

  6. Checks for a short circuit to ground condition in the RF position supply.

    7.

  7. Checks for a short circuit condition between the LR position supply and ground.

    8.

  8. Checks for a short circuit condition between the RR position supply and ground.

    9.

  9. Checks for a short circuit condition between the LF position supply and ground.

    10.

  10. Checks for a short circuit condition between the RF position supply and ground.

    11.

  11. Checks for a short circuit to voltage condition in the LR position supply.

    12.

  12. Checks for a short circuit to voltage condition in the RR position supply.

    13.

  13. Checks for a short circuit to voltage condition in the LF position supply.

    14.

  14. Checks for a short circuit to voltage condition in the RF position supply.

Step

Action

Value(s)

Yes

No

1

Was the CVRSS System Check performed?

--

Go to Step 2

Go to Road Sensing Suspension Diagnostic System Check

2

  1. Turn the ignition ON with the engine off.
  2. Measure the voltage at pin A3 by backprobing the CVRSS control module.

Is the measurement less than the specified value?

6 V

Go to Step 4

Go to Step 3

3

Is the measurement greater than the specified value?

9 V

Go to Step 20

Go to Step 28

4

  1. Turn the ignition OFF.
  2. Disconnect CVRSS control module connector C2.
  3. Check for a continuity to ground condition on pin A3 of CVRSS connector C2 (harness side).

Is a short circuit to ground condition present?

--

Go to Step 5

Go to Step 6

5

Repair the short circuit to ground condition.

Is the repair complete?

--

Go to Road Sensing Suspension Diagnostic System Check

--

6

Check for continuity to ground on pin A5 of CVRSS connector C2 (harness side).

Is a short circuit to ground condition present?

--

Go to Step 7

Go to Step 8

7

Repair the short circuit to ground condition.

Is the repair complete?

--

Go to Road Sensing Suspension Diagnostic System Check

--

8

Check for continuity to ground on pin A8 of CVRSS connector C2 (harness side).

Is a short circuit to ground condition present?

--

Go to Step 9

Go to Step 10

9

Repair the short circuit to ground condition.

Is the repair complete?

--

Go to Road Sensing Suspension Diagnostic System Check

--

10

Check for a continuity to ground condition on pin A10 of CVRSS connector C2 (harness side).

Is a short circuit to ground present?

--

Go to Step 11

Go to Step 12

11

Repair the short circuit to ground condition.

Is the repair complete?

--

Go to Road Sensing Suspension Diagnostic System Check

--

12

Check for continuity between pin A3 and pin B3 of CVRSS connector C2 (harness side).

Is a short circuit to sensor ground condition present?

--

Go to Step 13

Go to Step 14

13

Repair the short circuit to sensor ground condition.

Is the repair complete?

--

Go to Road Sensing Suspension Diagnostic System Check

--

14

Check for continuity between pin A5 and pin B5 of the CVRSS connector C2 (harness side).

Is a short circuit to sensor ground condition present?

--

Go to Step 15

Go to Step 16

15

Repair the short circuit to sensor ground condition.

Is the repair complete?

--

Go to Road Sensing Suspension Diagnostic System Check

--

16

Check for continuity between pin A8 and pin B8 of CVRSS connector C2 (harness side).

Is a short circuit to sensor ground condition present?

--

Go to Step 17

Go to Step 18

17

Repair the short circuit to sensor ground condition.

Is the repair complete?

--

Go to Road Sensing Suspension Diagnostic System Check

--

18

Check for continuity between pin A10 and pin B10 of CVRSS connector C2 (harness side).

Is a short circuit to sensor ground condition present?

--

Go to Step 19

Go to Step 28

19

Repair the short circuit to sensor ground condition.

Is the repair complete?

--

Go to Road Sensing Suspension Diagnostic System Check

--

20

  1. Turn the ignition OFF.
  2. Disconnect CVRSS control module connector C2.
  3. Turn the ignition ON with the engine off.
  4. Measure the voltage between pin A3 of CVRSS connector C2 (harness side) and ground.

Is the measurement greater than the specified value?

10 V

Go to Step 21

Go to Step 22

21

Repair the short circuit to voltage condition in CKT 431.

Is the repair complete?

--

Go to Road Sensing Suspension Diagnostic System Check

--

22

Measure the voltage between pin A5 of CVRSS connector C2 (harness side) and ground.

Is the voltage greater than 10 volts?

--

Go to Step 23

Go to Step 24

23

Repair the short circuit to voltage condition in CKT 431.

Is the repair complete?

--

Go to Road Sensing Suspension Diagnostic System Check

--

24

Measure the voltage between pin A8 of CVRSS connector C2 (harness side) and ground.

Is the measurement greater than the specified value?

10 V

Go to Step 25

Go to Step 26

25

Repair the short circuit to voltage condition in CKT 431.

Is the repair complete?

--

Go to Road Sensing Suspension Diagnostic System Check

--

26

Measure the voltage between pin A10 of CVRSS connector C2 (harness side) and ground.

Is the measurement greater than the specified value?

10 V

Go to Step 27

Go to Step 28

27

Repair the short circuit to voltage condition in CKT 431.

Is the repair complete?

--

Go to Road Sensing Suspension Diagnostic System Check

--

28
  1. Turn the ignition OFF.
  2. Replace the CVRSS control module. Refer to Electronic Suspension Control Module Replacement .
  3. Install all of the connectors and components that were removed.
  4. Install the scan tool.
  5. Turn the ignition ON with the engine off.

    6. Important: The controller must be calibrated.

  6. Calibrate the CVRSS service controller using the scan tool. Refer to Electronic Suspension Control Module Calibration .

Is the CVRSS control module calibrated?

--

Go to Road Sensing Suspension Diagnostic System Check

--