3. Measure The Resistance Of The Siren Signal Output Circuit

Turn the ignition off.

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

Fig 1: Measuring Resistance Between Ground & Siren Output Circuit At Siren Harness Connector

Courtesy of DAIMLERCHRYSLER CORP.

Is the resistance below 10K ohms? 

1. Yes  >> Repair the Siren Signal Output circuit for a short to ground.

   See VTSS VERIFICATION TEST  .

2. No  >> Replace the Siren.

   See VTSS VERIFICATION TEST  .