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Charging System - Generators & Regulators Lincoln Town Car III

Charging System 1 illustration ~1159 words

DESCRIPTION

System consists of a 130-amp generator, voltage regulator, battery, warning indicator, related fuses and wiring. Warning indicator illuminates with ignition on, engine off as a bulb-check. Voltage regulator is integral type and cannot be serviced separately.

BELT TENSION

Vehicles are equipped with automatic drive belt tensioner. Drive belt does not require adjustment. Inspect condition and tension of generator drive belt prior to performing any on-vehicle charging system tests. Replace belt and/or repair tensioner mechanism if necessary.

TROUBLE SHOOTING

Note. See TROUBLE SHOOTING article in GENERAL INFORMATION.

PRELIMINARY CHECKS

  1. Verify battery condition.
  2. Inspect accessory drive belt and tensioner.
  3. Check all connections for looseness or corrosion.
  4. Inspect Gray fusible links, located near battery junction box.
  5. Inspect battery junction box fuses No. 2 (40-amp), and No. 13 (15-amp). Inspect central junction box fuse No. 12 (15-amp).

PARASITIC DRAW TEST

Connect ammeter to negative battery cable according to tool manufacturer's instructions. With all accessories off, doors closed and key out of ignition, current drain should be less than 50 milliamps. To locate the cause of current drains greater than 50 milliamps, remove fuses one at a time until current draw is within specification. Repair appropriate circuit, and check system operation.

BATTERY LOAD TEST

Connect battery tester according to tool manufacturer's instructions. Load test battery at approximately one-half cold-cranking amperage rating for 15 seconds while observing battery voltage. If voltage reading is 9.6 volts or more, battery is okay. If voltage reading is less than 9.6 volts, charge battery and retest. If loaded battery voltage is still less than 9.6 volts after charging battery, replace battery.

GENERATOR LOAD TEST

Ensure drive belt is in good condition. Connect charging system load tester in accordance with manufacturer's instructions. Start and run engine at 2000 RPM, and apply load until generator output levels off. Generator output should be at least 87 amps at 2000 RPM. With engine running, turn A/C (if equipped) and headlights on, and turn blower motor to high speed. Increase engine speed to 2000 RPM. Voltage should increase a minimum of .5 volt above base voltage.

GENERATOR NO-LOAD TEST

Connect voltmeter positive lead to B+ terminal on generator and negative lead to ground. Start and run engine at 2000 RPM with all accessories off. Read voltmeter when voltage stabilizes. Voltage should be 13-15 volts.

INTRODUCTION

Identify symptom and perform appropriate test. See SYMPTOM INDEX table.

SymptomPerform Test
Warning Indicator On With Engine Running, System Is Not ChargingA
System OverchargesB
Warning Indicator On With Engine Running, System Is ChargingC
Warning Indicator Off With Ignition OnD
Warning Indicator Flickers Or Is IntermittentE

SYMPTOM INDEX

TEST A: WARNING INDICATOR ON WITH ENGINE RUNNING, SYSTEM IS NOT CHARGING

  1. Remove and inspect battery junction fuses No. 2 (40-amp) and No. 13 (15-amp), and central junction box fuse No. 12 (15-amp). Inspect Gray fusible links. Replace fuse(s) and/or fusible links as necessary. If okay, go to next step.
  2. Measure voltage of Black/Orange wire at generator B+ terminal (component side). If battery voltage is present, go to next step. If battery voltage is not present, repair open in Black/Orange wire between generator and battery junction box. See «WIRING DIAGRAMS»(/lincoln/town-car/iii-1997-2003/remont/charging-system/#charging-system-generators-regulators) . Retest system operation.
  3. Disconnect generator 3-pin connector. Measure voltage of Yellow/White wire at generator connector terminal "A". If battery voltage is present, go to next step. If battery voltage is not present, repair open in Yellow/White wire between generator and battery junction box. See «WIRING DIAGRAMS»(/lincoln/town-car/iii-1997-2003/remont/charging-system/#charging-system-generators-regulators) . Retest system operation.
  4. Turn ignition on. Measure voltage of Light Green/Red wire at generator terminal "I". If battery voltage is present, go to next step. If battery voltage is not present, repair open in Light Green/Red wire between generator and instrument panel. See «WIRING DIAGRAMS»(/lincoln/town-car/iii-1997-2003/remont/charging-system/#charging-system-generators-regulators) . Retest system operation.
  5. Start engine. With engine running, turn headlights and rear defogger on, and turn blower motor to high speed. Increase engine speed to 2000 RPM. Measure voltage drop by connecting voltmeter positive lead to positive battery terminal and negative lead to generator terminal B+. If voltage drop is less than .5 volt, replace generator. See «GENERATOR»(/lincoln/town-car/iii-1997-2003/remont/charging-system/#charging-system-generators-regulators) under REMOVAL & INSTALLATION. If voltage drop is greater than .5 volt, repair high resistance in Black/Orange wire between generator and battery junction box. See «WIRING DIAGRAMS»(/lincoln/town-car/iii-1997-2003/remont/charging-system/#charging-system-generators-regulators) .

TEST B: SYSTEM OVERCHARGES

  1. Disconnect generator 3-pin connector. Connect voltmeter positive lead to generator connector terminal "A" (Yellow/White wire) and negative lead to positive battery cable. Turn ignition on. Measure voltage drop of Yellow/White wire between generator connector terminal "A" and positive battery terminal. If voltage drop is less than .5 volt, go to next step. If voltage drop is greater than .5 volt, repair high resistance in Yellow/White wire between generator and battery junction box. See «WIRING DIAGRAMS»(/lincoln/town-car/iii-1997-2003/remont/charging-system/#charging-system-generators-regulators) .
  2. Ensure battery ground connections are clean and tight. Ensure generator mounting surfaces are clean and fasteners are tight. Clean and tighten as necessary. Retest system operation. If connections are okay, replace generator. See «GENERATOR»(/lincoln/town-car/iii-1997-2003/remont/charging-system/#charging-system-generators-regulators) under REMOVAL & INSTALLATION.

TEST C: WARNING INDICATOR ON WITH ENGINE RUNNING, SYSTEM IS CHARGING

Disconnect generator 3-pin connector. Turn ignition on and observe warning indicator. If warning indicator illuminates, repair short to ground in Light Green/Red wire between generator and instrument panel. See WIRING DIAGRAMS . If warning indicator does not illuminate, replace generator. See GENERATOR under REMOVAL & INSTALLATION.

TEST D: WARNING INDICATOR OFF WITH IGNITION ON

Disconnect generator 3-pin connector. Using a fused (15-amp) jumper wire, ground Light Green/Red wire at generator terminal "I". Turn ignition on, and observe warning indicator. If warning indicator illuminates, replace generator. See GENERATOR under REMOVAL & INSTALLATION. If warning indicator does not illuminate, repair warning indicator as necessary. See ANALOG INSTRUMENT PANELS - TOWN CAR article in ACCESSORIES & EQUIPMENT.

TEST E: WARNING INDICATOR FLICKERS OR IS INTERMITTENT

  1. Turn ignition off. Inspect all generator and battery connections for looseness, corrosion and bent terminals. Clean and tighten connections as necessary. If connections are clean and tight, go to next step.
  2. Start engine. With engine running, inspect battery junction fuse No. 13 (15-amp) and central junction box fuse No. 12 (15-amp) by wiggling fuses and noting warning indicator operation. If warning indicator flickers, repair loose fuse connection(s) as necessary. Retest system operation. If warning indicator does not flicker, go to next step.
  3. Turn ignition off. Connect a fused (15-amp) jumper wire to positive battery terminal, and backprobe generator connector terminal "A". Start engine. With engine running, observe warning indicator. If warning indicator flickers, replace generator. See «GENERATOR»(/lincoln/town-car/iii-1997-2003/remont/charging-system/#charging-system-generators-regulators) under REMOVAL & INSTALLATION. If warning indicator does not flicker, repair loose connections in circuit. Retest system operation.

REMOVAL & INSTALLATION

CAUTIONWhen battery is disconnected, vehicle computer and memory systems may lose memory data. Driveability problems may exist until computer systems have completed a relearn cycle. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION before disconnecting battery.

Disconnect negative battery cable. Remove rear engine cover screw. Pull cover forward to disengage front clips, and remove cover. Disengage push pins and pull harness away from top of generator. Remove 4 bolts and upper generator bracket. Disconnect wiring from generator. Remove drive belt. Remove attachment bolts, and generator from vehicle. To install, reverse removal procedure. Tighten fasteners to specification. See TORQUE SPECIFICATIONS .

TORQUE SPECIFICATIONS

ApplicationFt. Lbs. (N.m)
Generator Mounting Bolts15-22 (20-30)
INCH Lbs. (N.m)
Generator Support Bracket71-106 (8-12)
Generator Terminal B+ Nut62-79 (7-9)

TORQUE SPECIFICATIONS

Charging System Wiring Diagram (Town Car). Scheme 1

Scheme 1: Charging System Wiring Diagram (Town Car)
Scheme 1: Charging System Wiring Diagram (Town Car)