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For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 1999 🢒 Eldorado 🢒 Suspension 🢒 Road Sensing Suspension (RSS) 🢒 DTC C1785 ICCS2 DL Right Output Short CKT to GND

Object Number: 258352 Size: SF

Circuit Description

The CVRSS control module estimates the road surface and communicates that information to the Electronic Brake and Traction Control Module (EBTCM) using the ICCS2 Datalink Left and Right Outputs. The EBTCM uses this information to provide improved rough-road braking performance.

Conditions for Setting the DTC

The DTC is set when the CVRSS control module measures a feedback voltage less than a preset threshold during an ICCS2 Datalink Right Output OFF state.

The DTC turns HISTORY when the CVRSS control module no longer senses a low feedback voltage during five (5) consecutive ICCS2 Datalink Right Output OFF states.

Action Taken When the DTC Sets
    • Both of the ICCS2 Datalink Outputs are set to default output states.
    • The SERVICE RIDE CONTROL message is displayed.

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. This step determines if the fault is due to a short circuit to ground condition or an open circuit condition in CKT 791.

    2.

  2. This step checks for a short circuit to ground condition in CKT 791.

    3.

  3. This step checks for an open circuit condition in CKT 791.

    4.

  4. This step determines if the short circuit to ground condition is in the wiring or with the EBTCM.

    5.

  5. This step checks for intermittent open circuit conditions.

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 OFF.
  2. Disconnect CVRSS control module connector C1.
  3. Turn the ignition ON with the engine off.
  4. Measure the voltage between pin D14 of the CVRSS control module connector (harness side) and ground.

Is the measurement greater than the specified value?

10 V

Go to Step 8

Go to Step 3

3

Check for continuity between pin D14 of the CVRSS control module connector (harness side) and ground.

Is a short circuit to ground condition (continuity) present?

--

Go to Step 5

Go to Step 4

4

  1. Disconnect EBTCM connector C2.
  2. Check for continuity between pin D14 of the CVRSS control module connector and pin 2 of the EBTCM connector.

Is there continuity?

--

Go to Step 11

Go to Step 6

5

  1. Disconnect EBTCM connector C2
  2. Check for continuity between CKT 791 and ground.

Is there continuity?

--

Go to Step 7

Go to Step 11

6

Repair the open circuit condition in CKT 791.

Is the repair complete?

--

Go to Road Sensing Suspension Diagnostic System Check

--

7

Repair the short circuit to ground condition in CKT 961.

Is the repair complete?

--

Go to Road Sensing Suspension Diagnostic System Check

--

8

Check the appropriate terminal and/or connection for corrosion or improper seating.

Is the connection good?

--

Go to Step 10

Go to Step 9

9

Correct the poor connection condition.

Is the repair complete?

--

Go to Road Sensing Suspension Diagnostic System Check

--

10
  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

--

11
  1. Turn the ignition OFF.
  2. Replace the EBTCM. Refer to Electronic Brake Control Module Replacement in Antilock Brake System.

Is the repair complete?

--

Go to Road Sensing Suspension Diagnostic System Check

--