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Circuit Test STP - Switch To Power: Notes

Fig 1: Switch Circuit & Connector Terminal ID
G92J04111
NOTE: Enter this test only when directed here from SWITCH MONITOR TEST. This test is intended to diagnose the following switches and circuits: Brake On-Off (BOO) switch, Cooling Fan Relay (FAN), Headlight (HLDT) switch, Rear Window Defrost (DEF) and Vehicle Start (VST) switch.
CIRCUIT PIN IDENTIFICATION (STP)

Circuit Breakout Box Pin No. ECA Pin Wire Color
1.8L
BOO 2 (1) 1O Green
DEF 30 1T Black/Blue
FAN (1) 22 (1) 1R Black/Green
HLDT 28 1U Red/Black
VST 5 1C Pink
2.2L Non-Turbo
A/T
BOO 2 1Q White/Green
DEF 34 1J Black/Blue
FAN 51 2D Black/Green
HLDT 32 1H White/Black
VST 23 1C Black/Pink
M/T
BOO 2 1O White/Green
DEF 30 1T Black/Blue
FAN 22 1R Black/Green
HLDT 28 1U White/Black
VST 5 1C Black/Pink
2.2L Turbo
BOO (1) 2 (1) 1Q White/Green
DEF 34 1J Black/Blue
FAN 51 2D Black/Green
HLDT 32 1H White/Black
VST 23 1C Black/Pink
(1) Available on manual transaxle models only.

1) Checking System Integrity  Visually check all wiring, connectors and components for damage, shorting or looseness. If fault is found, repair as necessary. If no fault is found, go to next step.

2) Checking Switch Signal  Install breakout box, leaving ECA disconnected. Turn ignition on. Measure voltage between breakout box test pin of component being tested and ground. See CIRCUIT PIN IDENTIFICATION (STP)  . Check voltage with component in ON and OFF positions. See SWITCH PERFORMANCE CHECK.

3)  Voltage should switch from 0-4 volts to 10-14 volts. If voltage is as specified and no other problem or code is found, replace ECA. If voltage is not as specified, measure voltage at switch connector terminal with component in ON and OFF positions.

4)  If voltage switches from 0-4 volts to 10-14 volts, repair open circuit between switch and ECA. If voltage does not switch from 0-4 volts to 10-14 volts, turn ignition off. Measure resistance between component test pin and the following: test pin No. 1, test pin No. 37, test pin No. 57 and ground. Resistance should be more than 10,000 ohms. If resistance is as specified, go to next step. If resistance is not as specified, repair appropriate circuit(s).

5)  Disconnect connector of switch being tested. Measure resistance between switch terminals. Resistance should be less than 5 ohms with switch closed and more than 10,000 ohms with switch open. If resistance is not as specified, replace switch. If resistance is as specified and no other problem or code is found, replace ECA.