Amplifier Test: Notes
CAUTION:
DO NOT
use a test light to perform amplifier tests, as excessive current draw will damage electronic components. Use only a voltmeter of 5000 ohm/volt rating or higher. "ON" Circuit Test (Aerostar, Bronco II & Ranger)
- Turn ignition switch to "ON" position and connect a voltmeter between White/Purple wire and ground in 6-pin connector at amplifier. Connect voltmeter between Lt. Blue/Black wire and ground at amplifier 6-pin connector.
- Voltmeter should read battery voltage when "ON" switch is depressed and held. If voltage is not available, perform control switch test. Release "ON" switch. Voltmeter should read 7.8 volts. If meter reads zero volts, check ground (Black wire) on amplifier.
- If there is no ground on amplifier, check system ground connection and wiring. Also check No. 1 and 6 fuses and/or temporarily install a known good amplifier and recheck for good "ON" circuit.