Component Testing: Servo
- Locate amplifier 8-pin connector behind right side of dash, above glove box. Disconnect amplifier 8-pin connector. Measure resistance between specified wire terminals of amplifier connector. See SERVO RESISTANCE table. If resistances are as specified, go to next step. If resistances are not as specified, go to step 3).SERVO RESISTANCE
Wire Color Ohms Orange/Yellow - Gray/Black 40-70 Orange/Yellow - White/Pink 100-150 Purple/Light Blue - Brown/Light Green 35,000-70,000 Purple/Light Blue - Yellow/Red 15,000-35,000 Yellow/Red - Brown/Light Green 15,000-35,000 - Compare resistance measurement between Purple/Light Blue wire terminal and Yellow/Red wire terminal of amplifier connector with resistance measurement between Yellow/Red wire terminal and Brown/Light Green wire terminal of amplifier connector. If resistance measurements differ more than 5000 ohms and vehicle has a surging problem, go to next step. If resistance measurements do not differ more than 5000 ohms and vehicle does not have a surging problem, go to step 4).
- Disconnect servo 6-pin connector. Ensure terminals are clean. Measure resistance between specified wire terminals of servo connector. See SERVO RESISTANCE table. If resistances are as specified, check wiring for continuity. Repair as necessary. If resistances are not as specified, replace servo and retest.
- Disconnect servo from amplifier. Start engine. Ensure vacuum to servo is at least 2.5 in. Hg. Connect battery positive lead to Orange/Yellow wire of servo. Connect White/Pink wire of servo to ground. Momentarily connect Gray/Black wire of servo to ground.
- Servo arm should pull in and engine speed should increase when Gray/Black wire of servo is connected to ground. Disconnect White/Pink wire from ground. Servo should release. Replace servo if responses are not as specified.