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Home >> Volvo >> 2003 >> XC90 Base, AWD >> Repair and Diagnosis (Single Page) >> Electrical >> Body Electrical >> Rear Electronic Module (Rem) And Upper Electronic Module (UEM) Diagnostic Trouble Codes >> UEM-0004: Siren. Communication Fault >> Communication Fault >> Checking For Open-Circuits And Short-Circuits
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Checking For Open-Circuits And Short-Circuits

Check that the fuses in the fusebox in the passenger compartment are intact.

Check the cable between control module terminal #21 and siren terminal #2. Check for a short-circuit to ground. Check for an open-circuit. Check for a short-circuit to supply voltage.

Check the wiring from the fuse in the passenger compartment to siren connector terminal #1. Check for an open-circuit. Check for a short-circuit to ground.

Other information: 

Remedy as necessary.

Fig 1: Identifying Connector Terminals
GLL104071Courtesy of VOLVO CARS CORPORATION
Fig 2: Identifying Ohms Display
GLL101042Courtesy of VOLVO CARS CORPORATION
Fig 3: Locating Fuse Holder (Passenger Compartment)
GLL104037Courtesy of VOLVO CARS CORPORATION

Was a fault detected?