Checking the 30-supply to the control module

WARNING: This page is about a different car, the 2004 Volvo S40, 2003 Volvo S40, 2002 Volvo S40, 2001 Volvo S40, and 2000 Volvo S40. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Identifying Ignition OFF

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Fig 2: Connecting Control Module

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Ignition off
Reconnect the control module.
Connect a voltmeter between terminals #1 and #3 on the breakout box.

Fig 3: Breakout Box
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Fig 4: Identifying Voltage Display
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The voltmeter should read approximately battery voltage.

OK
Refer to Checking the function of the ABS hydraulic modulator
NOT OK
Refer to Checking for an open-circuit