Test 8: Valve Relay Problem
- Turn ignition off. Remove TCS valve relay. Relay is the smallest of the 2 relays mounted on hydraulic unit. Measure resistance between relay terminals "A" and "B". See Fig 1
. If resistance is 80-100 ohms, go to next step. If resistance is not 80-100 ohms, replace relay.
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- Measure resistance between relay terminals "C" and "E". Resistance should be infinite. Measure resistance between relay terminals "C" and "F". Resistance should be less than one ohm. Apply battery voltage between relay terminals "A" and "B". Resistance between terminals "C" and "F" should be infinite and resistance between terminals "C" and "E" should be less than one ohm. If resistance is as specified, go to next step. If resistance is not as specified, replay relay.
- Measure resistance between relay terminals "B" and "F". If resistance is not infinite, replay relay. If resistance is infinite, measure voltage between ground and terminal No. 1 at relay harness connector. If voltage is zero volts, go to next step. If voltage is more than zero volts, repair wiring harness as necessary.
- Measure voltage between ground and terminal No. 3 at relay harness connector. If battery voltage does not exist, repair wiring harness as necessary. If battery voltage exists, turn ignition on. Measure voltage between ground and terminals No. 1 and 3. If battery voltage exists, go to next step. If battery voltage does not exist, repair wiring harness as necessary.
- Turn ignition off. Disconnect ABS/TCS control unit connectors. Measure resistance between ground and terminal No. 6 at relay harness connector. If resistance is one ohm or less, go to next step. If resistance is more than one ohm, repair wiring harness as necessary.
- Measure resistance between ground and terminal No. 6 at ABS/TCS control unit 16-pin harness connector. See Figure
. Resistance should be infinite. Install relay. Measure resistance between ground and terminal No. 6. Resistance should be one ohm or less. If resistance is as specified, go to next step. If resistance is not as specified, repair wiring harness as necessary.
- Measure resistance between terminals No. 1 at ABS/TCS control unit 8-pin harness connector and No. 1 at ABS/TCS control unit 16-pin connector. If resistance is 80-100 ohms, go to next step. If resistance is not 80-100 ohms, repair wiring harness as necessary.
- Turn ignition on. Measure voltage between ground and terminal No. 1 at ABS/TCS control unit 16-pin harness connector. If battery voltage exists, replace ABS/TCS control unit. If battery voltage does not exist, repair wiring harness as necessary.