Diagnostic Test

1) CHECK FOR ACTIVE DTC
NOTE: If B2104 or B2105 are active, perform those tests first before proceeding.

NOTE: Check the rear PDC fuses. An open fuse can cause this DTC to set. If open refer to the wiring diagrams to help isolate a possible shorted circuit.

With the scan tool, read the active DTC's.

Cycle the ignition switch from off to on, leaving the ignition on for a minimum of 90 seconds.

With the scan tool, read the active DTC's.

Does the scan tool display this DTC as active?

Yes
1. Go To step 2).
No
1. If the DTC is stored, check for an intermittent condition. Visually inspect the related wiring harness connectors. Look for broken, bent, pushed out, or corroded terminals.
2) CHECK THE (F20) FUSED IGNITION SWITCH OUTPUT CIRCUIT FOR AN OPEN
Turn the ignition off.

Remove the fused ignition switch output fuse from the rear PDC.

Turn the ignition on.

Measure the voltage of the (F20) Fused Ignition Switch Output circuit (input side of fuse).

Is the voltage above 10.0 volts?

Yes
1. Go To step 3).
No
1. Go To step 4).
3) (F202) FUSED IGNITION SWITCH OUTPUT CIRCUIT OPEN

Fig 1: Checking Fused Ignition Switch Output Circuit
Courtesy of DAIMLERCHRYSLER CORP.

Turn the ignition off.

Remove the FCM from the Power Distribution Module.

NOTE: Install the fuse in the rear PDC.

Turn the ignition on.

Measure the voltage of the (F202) Fused Ignition Switch Output circuit.

Is the voltage above 10.0 volts?

Yes
1. Inspect the wiring and connectors for damage or shorted circuits. If OK, replace and program the Front Control Module in accordance with the service information.
2. Perform BODY VERIFICATION TEST - VER 1 . (Refer to BODY VERIFICATION TEST - VER 1) .
No
1. Repair the (F202) Ignition Switch Output circuit for an open between the rear PDC and the front PDM.
2. Perform BODY VERIFICATION TEST - VER 1 . (Refer to BODY VERIFICATION TEST - VER 1) .
4) (A106) FUSED B+ CIRCUIT OPEN

Fig 2: Checking Fused B+ Circuit
Courtesy of DAIMLERCHRYSLER CORP.

Turn the ignition off.

Disconnect the Ignition Switch harness connector.

Measure the voltage of the (A106) Fused B+ circuit.

Is the voltage above 10.0 volts?

Yes
1. Repair the (F20) Fused Ignition Switch Output circuit for an open between the Ignition Switch and the rear PDC. If OK, replace the Ignition Switch in accordance with the service information.
2. Perform BODY VERIFICATION TEST - VER 1 . (Refer to BODY VERIFICATION TEST - VER 1) .
No
1. Repair the (A106) Fused B+ circuit for an open.
2. Perform BODY VERIFICATION TEST - VER 1 . (Refer to BODY VERIFICATION TEST - VER 1) .