Amplifier Test

CAUTION: When performing this test use a voltmeter with a 5000 ohm/volt rating or higher. Using a test lamp may damage amplifier due to excessive current draw.

"ON" Circuit Test
1. Turn ignition switch to ON position.
2. Connect voltmeter between white/purple (circuit 296) and ground in six pin connector at amplifier. If voltmeter indicates battery voltage, proceed to step 3. If voltmeter does not indicate battery voltage, check fuse voltage, then repair circuit or replace fuse as necessary.
3. Connect a voltmeter to light blue/black (circuit 151) and ground at six pin connector at amplifier, then set speed control switch to ON position. If voltmeter indicates battery voltage, proceed to step 4. If voltmeter does not indicate battery voltage, refer to Control Switch Test. Control Switch Test
4. With voltmeter connected as in step 4, release ON button. If voltmeter reading is zero, proceed to step 5. If voltmeter reading is approximately 7.8 volts, ON circuit is engaged.
5. Check ground at amplifier (either black wire on amplifier six pin connector). If there is no ground on amplifier, check system ground wiring and connections. Also check 20 amp fuse and circuit breaker and repair or replace as necessary. If ground is present at amplifier, proceed to step 6.
6. If voltmeter still reads zero, substitute, but do not install a known good amplifier, then recheck ON circuit operation.

Brake Circuit Test
1. Connect ohmmeter between light green wire (circuit 511) and ground at six pin connector.
2. Resistance should be less than 5 ohms.
3. If resistance is greater than 5 ohms, check for improper wiring, burnt out stop lamps or clutch switch malfunction.

OFF Circuit Test
1. Turn ignition switch to RUN position.
2. Connect a voltmeter to light blue/black wire (circuit 151), depress OFF switch on steering wheel, then read voltage.
3. Voltage should drop to zero indicating ON circuit is de-energized.
4. If voltage does not drop to zero, perform Control Switch Test. Control Switch Test
5. If switches are checked and found to be satisfactory, substitute amplifier with a known good amplifier, then repeat test.

SET/ACCEL Circuit Test
1. Turn ignition switch to ON position.
2. Connect a voltmeter between light blue/black wire (circuit 151) and ground at six pin connector.
3. Depress and hold SET/ACCEL button on steering wheel. Voltmeter should read approximately 4.5 volts.
4. Rotate steering wheel and watch for voltmeter fluctuations. If voltage varies more than 0.5 volts, perform Control Switch Test. Control Switch Test

COAST Circuit Test
1. Turn ignition switch to ON position.
2. Connect a voltmeter between light blue/black wire (circuit 151) and ground at six pin connector.
3. Depress and hold COAST button on steering wheel. Voltmeter should read approximately 1.5 volts.
4. Rotate steering wheel back and forth and check for voltmeter fluctuations. If voltage varies more than 0.05 volts, perform Control Switch Test. Control Switch Test

RESUME Circuit Test
1. Turn ignition switch to ON position.
2. Connect a voltmeter between light blue/black wire (circuit 151) and ground at six pin connector.
3. Depress and hold RESUME button on steering wheel. Voltmeter should read approximately 6.5 volts.
4. Rotate steering wheel back and forth and check for voltmeter fluctuations. If voltage varies more than 0.05 volts, perform Control Switch Test. Control Switch Test
5. If all circuits are satisfactory, perform Servo Assembly Test, substituting a known good amplifier. Do not substitute a known good amplifier until servo assembly test has been successfully completed. Servo Assembly Test