Diagnostic Test

1) MEASURE THE RESISTANCE OF THE SIREN SIGNAL OUTPUT CIRCUIT

Fig 1: Measuring Resistance Of Siren Signal Output Circuit
Courtesy of DAIMLERCHRYSLER CORP.

Turn the ignition off.

Disconnect the CLP/SSM harness connector.

Disconnect the Siren harness connector.

NOTE: Check connectors - Clean/repair as necessary.

Measure the resistance of the Siren Signal Output circuit from the CLP/SSM harness connector to the Siren harness connector.

Is the resistance below 5.0 ohms?

Yes
1. Go to step 2).
No
1. Repair the Siren Signal Output circuit for an open.
2. Perform VTSS VERIFICATION TEST .
2) MEASURE THE VOLTAGE OF THE SIREN SIGNAL OUTPUT CIRCUIT

Fig 2: Measuring Voltage Of Siren Signal Output Circuit
Courtesy of DAIMLERCHRYSLER CORP.

Turn the ignition on.

Measure the voltage of the Siren Signal Output circuit at the Siren harness connector.

Is voltage present?

Yes
1. Repair the Siren Signal Output circuit for a short to voltage.
2. Perform VTSS VERIFICATION TEST .
No
1. Go to step 3).
3) MEASURE THE RESISTANCE OF THE SIREN SIGNAL OUTPUT CIRCUIT

Fig 3: Measuring Resistance Of Siren Signal Output Circuit
Courtesy of DAIMLERCHRYSLER CORP.

Turn the ignition off.

Measure the resistance between ground and the Siren Signal Output circuit at the Siren harness connector.

Is the resistance below 10K ohms?

Yes
1. Repair the Siren Signal Output circuit for a short to ground.
2. Perform VTSS VERIFICATION TEST .
No
1. Replace the Siren.
2. Perform VTSS VERIFICATION TEST .