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HOMESERVICE MANUALSMERCURY1991TRACER BASE, 4D SEDAN, AUTOMATICREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 13 (ENGINE CONTROLS - TESTS W/CODES - EEC 1.8L)SELF-DIAGNOSTIC SYSTEMSWITCH MONITOR TESTANALOG VOM OR MIL
1991 Mercury Tracer Base, 4D Sedan, Automatic

Analog VOM Or MIL

1991 Mercury Tracer Base, 4D Sedan, AutomaticSECTION Analog VOM Or MIL
WARNING: This page is about a different car, the 1994 Mercury Tracer and 1994 Ford Escort. However, it is still accessible from the selected car via links, so may be relevant.

1)  Turn engine off and allow to cool. Turn all accessories off. Disconnect PCM STI jumper from ground. Place shift lever in Park (A/T) or Neutral (M/T).

2)  Reconnect jumper wire between ground and PCM STI terminal at DLC connector. Using VOM, connect positive (+) lead to SML terminal at DLC connector. See Figure . Connect negative (-) lead to engine ground.

3)  Turn ignition on. Operate input switches individually while watching VOM (or MIL). See SWITCH MONITOR TEST SPECIFICATIONS table. Ensure input switch is deactivated after each test. Leaving switch on while testing another switch may produce false results and cause misdiagnosis.

4)  If input switch fails test (reading on VOM is not as specified or MIL does not blink), perform related circuit test. See SWITCH MONITOR TEST SPECIFICATIONS table. If all input devices fail, check Switch Monitor Light (SML) circuit. See CIRCUIT TEST SML. If all input devices test okay and no code is stored in PCM memory, EEC self-diagnostic system test is complete.

SWITCH MONITOR TEST SPECIFICATIONS

Switch/Relay Condition Super Star II/VOM Indication Circuit Test(1)
A/C Switch A/C & Blower Switch On LED On/Less Than 1.5 Volts STG 
Blower Motor Switch Blower Switch On High LED On/Less Than 1.5 Volts STG 
Brake On/Off Switch Brake Pedal Depressed LED On/Less Than 1.5 Volts STP 
Engine Coolant Temp. Sensor (1.8L) Cooling Fan On Low(2) LED On/Less Than 1.5 Volts STP 
Headlight Switch Headlt. Sw. On LED On/Less Than 1.5 Volts STP 
Idle Switch Accelerator Pedal Depressed LED On/Less Than 1.5 Volts STG 
Knock Sensor Tap On Engine While Running LED On/Less Than 1.5 Volts KC
Manual Lever Position Switch (A/T) (3) LED On/Less Than 1.5 Volts STP 
Park/Neutral Position Switch/ Clutch Pedal Position Switch (M/T) Transaxle In Gear & Clutch Pedal Released LED On/Less Than 1.5 Volts STG 
Rear Defroster Switch Rear Defroster Switch On LED On/Less Than 1.5 Volts STP 
Wide Open Throttle Switch (M/T) Accelerator Pedal Fully Depressed LED Off/ 12 Volts STG 
(1) Proceed to circuit test indicated if Super Star II/VOM indication is incorrect. See CIRCUIT TESTS.

(2) To perform test, ground cooling fan if necessary.

(3) Set selector lever in "D", "L", "R" or overdrive.
RENDER: 1.0x

NO RELATED

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