Circuit Test VPWR - Vehicle Power

Fig 1: VPWR Circuit & Connector Terminal ID

NOTE: Enter this test only when directed here from CIRCUIT TESTS. To prevent replacement of good components, check for faults in the following non-EEC components: ignition switch, alternator, battery cables, ground straps or voltage regulator. This test is intended to diagnose only the following circuits: VPWR and GND.

CIRCUIT PIN IDENTIFICATION

Circuit	Breakout Box Pin No.	ECA Pin	Wire Color
1.8L
GND	39, 40, 44 & 60	2A	Black/Orange
GND	20	2B	Black/Orange
GND	16	2C	Black/Green
VPWR	37 & 57	1B	Yellow/Black
2.2L
Non-Turbo M/T
GND	39, 40, 44 & 60	2A	Black
GND	20	2B	Black
VPWR	37 & 57	1B	Red/Black
GND	16	2C	Black/Green
All Others
GND	39, 40, 44 & 60	3A	Black
GND	20	3B	Black
GND	16	3C	Black/Green
VPWR	37 & 57	1B	Red/Black

1) Checking Circuit Integrity Visually check all wiring, connectors and components for evidence of damage, shorting or looseness. If fault is found, repair as necessary. If no fault is found, check battery voltage and charge condition. Service as necessary, and go to next step.

2) Ground Circuit Check Turn ignition off, and install breakout box. Turn ignition on. Measure voltage between the following points.

VPWR Test Pin & Battery Ground
VPWR Test Pin & Each Ground Test Pin
VPWR Test Pin & Each ECA Ground Wire

If all measurements are greater than 10 volts, go to CIRCUIT TEST VREF. If any measurement is less than 10 volts, repair as necessary.

3) VPWR From Main Relay Turn ignition off. Disconnect main power relay 4-wire connector. Main relay is located inside engine compartment relay box. Using jumper wire, connect BATT, PWR and GND terminals to matching terminals in connector. Leave VPWR circuit disconnected.

4) Turn ignition on. Measure voltage between ground and VPWR terminal of main power relay connector. If voltage is more than 10 volts, repair VPWR circuit between main power relay and ECA. If voltage is less than 10 volts, measure voltage between ground and BATT terminal of main power relay connector.

5) If voltage is less than 10 volts, repair BATT circuit between main power relay and battery. If voltage is more than 10 volts, measure voltage between ground and PWR terminal of main power relay connector.

6) If voltage is less than 10 volts, repair PWR circuit between main power relay and ignition switch. If voltage is more than 10 volts, measure voltage between BATT terminal and GND terminal of main power relay connector. If voltage is less than 10 volts, repair main power relay ground wire. If voltage is more than 10 volts, ground circuit is okay. Replace main power relay.