GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The Control Module will monitor the lift/dive signal which is pulled low, then high, by the PCM. Pin C3 of the CCR Control Module is connected to the Powertrain control Module. The PCM pulls the signal low to indicate a hard acceleration (lift) or deceleration (dive). Upon a transition from a high to a low state, the CCR Control Module shall command the Sport mode and maintain it until a low to high transition is detected.

Conditions for Setting the DTC

If the Control Module does not see the low to high transition within 15 seconds after key on it suspects a lift/dive signal error, but waits until the test has failed on the second consecutive ignition cycle to set the error in memory.

Action Taken When the DTC Sets

  1. Record the lift/dive signal error.
  2. Turn on both driver select switch L.E.D.s
  3. The system recovers upon successful completion of the lift/dive signal power-on test at the beginning of the next ignition cycle.

Diagnostic Aids

Notes on Intermittents

Whenever checking the lift/dive signal, the ignition must be turned off then on twice for the code to reset.

If the car is put into crank while in gear, the CCR Control Module shuts off, but the PCM doesn't, so the lift/dive handshake is not performed and the code may be set.

Also, refer to Intermittents and Poor Connections .

Step

Action

Value(s)

Yes

No

1

  1. Perform the RTD Diagnostic System Check .
  2. Turn the ignition OFF.
  3. Backprobe control module pin C3 to pin D16 with a digital voltmeter.
  4. Turn the ignition ON.
  5. Monitor the voltage for at least 20 seconds.

Is the voltage always low?

--

Go to Step 2

Go to Step 7

2

  1. Disconnect the PCM connector 3.
  2. Check the voltage from control module pin C3 to pin D16.

Does the voltage stay low?

--

Go to Step 4

Go to Step 3

3

Replace the PCM.

Is the replacement complete?

--

Go to RTD Diagnostic System Check

--

4

Check for a short circuit to ground condition in CKT 1490.

Is the circuit OK?

--

Go to Step 5

Go to Step 6

5

Replace the control module. Refer to Electronic Suspension Control Module Replacement .

Is the replacement complete?

--

Go to RTD Diagnostic System Check

--

6

Repair the short circuit to ground condition in CKT 1490.

Is the repair complete?

--

Go to RTD Diagnostic System Check

7

Does the voltage start low and then go high for 10 seconds?

--

Go to Step 8

Go to Step 9

8

Normal operation. Check for intermittents. Refer to Intermittents and Poor Connections .

Were any intermittents found?

--

Go to Intermittents and Poor Connections

Go to RTD Diagnostic System Check

9

Jump PCM pin 3E6 to ground and continue to monitor the voltage at control module pin C3.

Does the voltage stay high?

--

Go to Step 11

Go to Step 10

10

Replace the PCM.

Is the replacement complete?

--

Go to RTD Diagnostic System Check

--

11

Check for an open circuit condition or short circuit to battery condition in circuit 1490.

Was an open circuit condition or short circuit to battery condition found in CKT 1490?

--

Go to Step 12

Go to Step 13

12

Repair CKT 1490.

Is the repair complete?

--

Go to RTD Diagnostic System Check

--

13

Replace the module. Refer to Electronic Suspension Control Module Replacement .

Is the replacement complete?

--

Go to RTD Diagnostic System Check

--