[Paul]

Originally Posted by particlewave

Yes, the brown/blue wire needs to be grounded or the alarm will sound.
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Take it from an engineer; a "test light" is antiquated and doesn't tell you anything about power (actual current and voltage), only that you are completing a circuit. A multi meter is much more useful.

The way he is using a voltmeter tells him nothing about current.

On my 98 the alarm sounds when the radio alarm wire is grounded. Don't know what year his car is....guessed an early car since he is replacing a CDR-210.