GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2002 🢒 Eldorado 🢒 Body and Accessories 🢒 Theft Deterrent 🢒 DTC B2711

Circuit Description

The instrument panel cluster (IPC) supplies a 5 volt signal and a ground circuit for the PASS-Key® system. This allows the IPC to detect PASS-Key® resistance values. Inserting the PASS-Key® , with resistor pellet, in the ignition lock cylinder completes the PASS-Key® circuit. Contacts in the ignition lock cylinder mate with the pellet contacts. The IPC compares the resistance value of the key pellet to the valid resistance programmed into the IPC. If the proper resistance value is read, the IPC allows the engine to start. If the resistance value is incorrect, a malfunction is present and a DTC will set.

Conditions for Setting the DTC

The DTC will set under the following conditions:

    • B2710 indicates that an open or zero resistance value was measured from the key pellet prior to obtaining a valid resistance measurement.
    • B2711 indicates that an open or zero resistance value was measured from the key pellet following a valid resistance measurement.

Action Taken When the DTC Sets
    • When DTC B2710 is set as current, the IPC displays the STARTING DISABLED, REMOVE IGNITION KEY message on the driver message center and prevents the vehicle from starting.
    • When DTC B2711 is set as current, the IPC displays the THEFT SYSTEM PROBLEM, CAR MAY NOT RESTART message on the driver message center and allows the vehicle to continue to run.

Conditions for Clearing the DTC
    • This DTC requires an ignition cycle in order to change from current to history.
    • The IPC detects a valid PASS-Key® resistance value on the PASS-Key® signal circuit.
    • A history DTC will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present.
    • Use a scan tool.

Diagnostic Aids
    • If the key resistor pellet is incorrect, the engine will not start. This state will last about 3 minutes. If a key is inserted, or the ignition is turned ON again before the 3 minute time frame is complete, the timer will reset to 3 minutes. Disconnecting the battery will not clear the timer sequence, but the timer will reset to 3 minutes when the battery power is restored. Even if a proper key is inserted during one of the time periods, the vehicle will not start until the total time period has elapsed.
    • If there is a short between the PASS-Key® signal and ground circuit, or a short to ground on the PASS-Key® signal circuit, the vehicle will exhibit a no start condition.

Test Description

The number below refer to the steps number on the diagnostic table.

  1. This test verifies the integrity of the key resistor circuits between the ignition switch and the BCM.

Step

Action

Yes

No

1

Did you perform A Diagnostic System Check-Theft Deterrent?

Go to Step 2

Go to Diagnostic System Check - Theft Deterrent

2
  1. Install a scan tool.
  2. Turn ON the ignition with the ignition OFF.
  3. Select the Display DTCs function on the scan tool.

Does the scan tool display B2711 as a current DTC?

Go to Step 3

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

3

Inspect the ignition key for dirt or obvious damage.

Does the ignition key appear dirty or damaged?

Go to Step 9

Go to Step 4

4

  1. Turn off the ignition.
  2. Disconnect the steering column lock cylinder connector. (Note which half of the connector is the vehicle harness side and which half of the connector is the steering column harness side.
  3. Back out the terminals for the key resistor input circuit and key resistor reference ground circuit from the vehicle harness side of the connector.
  4. Reconnect the steering column lock cylinder .
  5. Connect a J 35628-A Vats/Passkey Interrogator using terminal adapters from a J 35616 to the key resistor input circuit and key resistor reference ground circuit.
  6. Insert the ignition key into the key code reader on the J 35628-A and note the code on the LCD display.
  7. Turn the rotary switch on the J 35628-A to the same code number as the ignition key.
  8. Attempt to start the vehicle.

Does the vehicle start?

Go to Step 6

Go to Step 5

5

Test the following circuits in the vehicle harness portion for an open or a short:

    • The key resistor input circuit
    • The key resistor reference ground circuit

Was a condition found and corrected?

Go to Step 12

Go to Step 7

6

Test the following circuits in the steering column harness portion for an open or a short:

    • The key resistor input circuit
    • The key resistor reference ground circuit

Was a condition found and corrected?

Go to Step 12

Go to Step 8

7

Inspect for poor connections at the harness connector of the instrument cluster. 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 12

Go to Step 11

8

Inspect for poor connections at the harness connector of the ignition lock cylinder. 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 12

Go to Step 10

9

Clean or replace the ignition key as necessary. Refer to Replacing Keys .

Did you complete the procedure?

Go to Step 12

--

10

Replace the ignition lock cylinder. Refer to Steering Column Lock and Ignition Switch Cylinder Replacement - On Vehicle in Steering Wheel and Column.

Did you complete the replacement?

Go to Step 12

--

11

Replace the instrument cluster. Refer to Instrument Cluster Replacement in Instrument Panel, Gages and Console.

Did you complete the repair?

Go to Step 12

--

12
  1. Use the scan tool in order to clear the DTCs.
  2. Attempt to start the vehicle.

Does the DTC reset?

Go to Step 2

System OK