B1612-PANEL ILLUMINATION CONTROL CIRCUIT

For a complete wiring diagram Refer to Section 8W.

When Monitored:
With the Ignition on, and the Panel Illumination active.
Set Condition:
Panel Illumination Status HIGH.

Possible Causes

(E2) PANEL LAMPS DRIVER CIRCUIT SHORTED TO GROUND

(E2) PANEL LAMPS DRIVER CIRCUIT SHORTED TO VOLTAGE

UPPER SWITCH BANK SHORTED TO GROUND

LOWER SWITCH BANK SHORTED TO GROUND

A/C HEATER CONTROL SHORTED TO GROUND

TRANSFER CASE SWITCH SHORTED TO GROUND

SHIFTER ASSEMBLY SHORTED TO GROUND

INSTRUMENT CLUSTER

Diagnostic Test

1. CHECK FOR AN ACTIVE DTC

Turn the ignition on.
With the scan tool, record and erase DTCs.
Activate the Panel Illumination.
Wait 30 seconds.
With the scan tool, read DTCs.

Is the DTC active?

Yes

Go To 2

The condition that caused this code to set is not present at this time. Check for an intermittent condition by inspecting the related wiring harness for chafed, pierced, pinched, and partially broken wires. Also inspect the related connectors for broken, bent, pushed out, spread, corroded, or contaminated terminals.
Perform BODY VERIFICATION TEST - VER 1. (Refer to BODY VERIFICATION TEST - VER 1).

2. CHECK THE UPPER SWITCH BANK FOR A SHORT TO GROUND

Turn the ignition off.
Disconnect the Upper Switch Bank harness connector.
Turn the ignition on.
Activate the Panel Illumination.
With the scan tool, read DTCs.

Does the scan tool display: B1612-PANEL ILLUMINATION CONTROL CIRCUIT?

Yes

Go To 3

Replace the Upper Switch Bank in accordance with the Service Information.
Perform BODY VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE)

3. CHECK THE LOWER SWITCH BANK FOR A SHORT TO GROUND

Turn the ignition off.
Disconnect the Lower Switch Bank harness connector.
Turn the ignition on.
Activate the Panel Illumination.
With the scan tool, read DTCs.

Does the scan tool display: B1612-PANEL ILLUMINATION CONTROL CIRCUIT?

Yes

Go To 4

Replace the Lower Switch Bank in accordance with the Service Information.
Perform BODY VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE)

4. CHECK THE A/C HEATER CONTROL FOR A SHORT TO GROUND

Turn the ignition off.
Disconnect the A/C Heater Control harness connector.
Turn the ignition on.
Activate the Panel Illumination.
With the scan tool, read DTCs.

Does the scan tool display: B1612-PANEL ILLUMINATION CONTROL CIRCUIT?

Yes

Go To 5

Replace the A/C Control in accordance with the Service Information.
Perform BODY VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE)

5. CHECK THE TRANSFER CASE SWITCH FOR A SHORT TO GROUND

Turn the ignition off.
Disconnect the Transfer Case Switch harness connector.
Turn the ignition on.
Activate the Panel Illumination.
With the scan tool, read DTCs.

Does the scan tool display: B1612-PANEL ILLUMINATION CONTROL CIRCUIT?

Yes

Go To 6

Replace the Transfer Case Switch in accordance with the Service Information.
Perform BODY VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE)

6. CHECK THE SHIFTER ASSEMBLY FOR A SHORT TO GROUND

Turn the ignition off.
Disconnect the Shifter Assembly harness connector.
Turn the ignition on.
Activate the Panel Illumination.
With the scan tool, read DTCs.

Does the scan tool display- B1612-PANEL ILLUMINATION CONTROL CIRCUIT?

Yes

Go To 7

Replace the Shifter Assembly in accordance with the Service Information.
Perform BODY VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE)

7. CHECK THE (E2) PANEL LAMPS DRIVER CIRCUIT FOR A SHORT TO GROUND

Turn the ignition off.
Disconnect the Instrument Cluster C2 harness connector.
With all the above components disconnected, measure the resistance to ground of the (E2) Panel Lamps Driver Circuit from the Instrument Cluster C2 harness connector.

Is the resistance less than 10K ohms?

Yes

Repair the (E2) Panel Lamps Driver circuit for a short to ground.

Perform BODY VERIFICATION TEST - VER 1. (Refer to BODY VERIFICATION TEST - VER 1).

Go To 8

8. CHECK THE (E2) PANEL LAMPS DRIVER CIRCUIT FOR AN OPEN

With all the above components disconnected, measure the resistance of the (E2) Panel Lamps Driver Circuit between the Instrument Cluster C2 harness connector and the Upper Switch Bank harness connector.

Is the resistance greater than 10K ohms?

Yes

Repair the (E2) Panel Lamps Driver circuit for an open.

Perform BODY VERIFICATION TEST - VER 1. (Refer to BODY VERIFICATION TEST - VER 1).

Go To 9

9. CHECK THE (E2) PANEL LAMPS DRIVER CIRCUIT FOR A SHORT TO VOLTAGE

Turn the ignition on.
With all the above components disconnected, measure the voltage of the (E2) Panel Lamps Driver Circuit from the Instrument Cluster C2 harness connector.

Is the voltage above 5.0 volts?

Yes

Repair the (E2) Panel Lamps Driver circuit for a short to voltage.

Perform BODY VERIFICATION TEST - VER 1. (Refer to BODY VERIFICATION TEST - VER 1).

Replace the Instrument Cluster in accordance with the Service Information.
Perform BODY VERIFICATION TEST - VER 1. (Refer to BODY VERIFICATION TEST - VER 1).