Alternator - W/integral Regulator - Motorcraft Ford Crown Victoria I

DESCRIPTION

Major components of the Motorcraft Integral Alternator-Regulator system with internal fan are: end frames, rotor, stator, rectifier assembly and electronic voltage regulator mounted on the rear of the alternator. (Scheme 1)

BELT TENSION

These vehicles use an automatic belt tensioner. Check condition of alternator drive belt prior to performing any on-vehicle charging system tests. Replace belt and tensioner mechanism if necessary.

ON-VEHICLE TESTING

GENERAL INSPECTION

Ensure battery posts and cables are clean and tight. Check drive belt tension. Ensure connections at alternator, regulator and engine ground are clean and tight. Check fuses and fusible links, replace as necessary.

Check condition of battery to see if battery has the ability to accept and hold a charge. If battery capacity meets requirements, charge battery before proceeding with testing to ensure battery is fully charged.

NO-LOAD TEST

1. Connect voltmeter positive lead to B+ terminal on alternator and negative lead to ground. Start and run engine at 1500 RPM with no electrical load (foot off brake and doors closed). Read voltmeter when voltage stabilizes. This may require waiting a few minutes. Voltage should be 13-15 volts.
2. If voltage increases to proper level, proceed to LOAD TEST. If voltage increases beyond proper level, proceed to OVERCHARGE CONDITION. If there is no voltage increase, proceed to LOW OR NO CHARGE CONDITION.

Scheme 1

LOAD TEST

1. Ensure drive belt is in good condition and properly tightened. Connect charging system load tester in accordance with manufacturer's instructions. Start and run engine at 2000 RPM and apply load until alternator output amperage levels off.
2. Record maximum alternator amperage output. See ALTERNATOR OUTPUT SPECIFICATIONS table for output values. If alternator output is within 20% of rated output amperage and voltage remains 12.5-14.5 volts, alternator output is okay. If alternator does not produce rated output, proceed with appropriate testing.

ALTERNATOR OUTPUT SPECIFICATIONS

OVERCHARGE CONDITION

1. If voltmeter indicates high voltage (more than 15.4 volts), turn ignition switch to ON position. Connect negative voltmeter lead to ground. Connect positive voltmeter lead to alternator output connection at starter solenoid. Record voltage.
2. Connect positive voltmeter lead to regulator "A" terminal screw on rear of alternator. (Scheme 1)and (Scheme 3). If a voltage difference between both locations exceeds 0.25 volt, repair high resistance condition in "A" circuit wiring.
3. If excessive voltage still exists, check ground connections for both alternator and regulator. Tighten regulator ground screws to 16-24 INCH lbs. (1.8-2.7 N.m.), and recheck output voltage.
4. If excessive voltage still exists, connect voltmeter negative lead to ground. Connect positive voltmeter lead first to regulator "A" terminal screw, then to "F" terminal screw. Record readings. Different voltages at each screw head indicates a short in the field circuit or a grounded rotor coil. To correct either condition, replace alternator.
5. If same voltage appears at both screw heads, no internal short to ground is indicated. Replace voltage regulator.

LOW OR NO CHARGE CONDITION

1. Unplug harness connector from regulator at rear of alternator. Connect ohmmeter between regulator "A" and "F" terminal screws. (Scheme 1)and (Scheme 3). If resistance is not greater than 2.4 ohms, a short in the field circuit or a grounded rotor coil is indicated. Replace alternator. If resistance is greater than 2.4 ohms, go to next step.
2. Reconnect regulator wiring plug. Connect negative voltmeter lead to ground. Contact positive voltmeter lead to regulator "A" terminal screw. If voltmeter does not indicate battery voltage, repair open or high resistance in "A" circuit wiring. Perform load test after repairs.
3. If battery voltage is indicated at "A" terminal screw, ensure ignition switch is in OFF position. Connect positive voltmeter lead to regulator "F" terminal screw. If battery voltage is present, go to step 4). If battery voltage is not present, replace alternator.
4. Turn ignition switch to ON position (engine off). With voltmeter negative lead to ground, contact positive lead of voltmeter to regulator "F" terminal screw. If voltmeter indicates 2 volts or less, go to next step. If voltage is greater than 2 volts, check circuit between "I" terminal and ignition switch. Repair if necessary. See "S" & "I" CIRCUIT TEST. If "I" circuit is okay, replace regulator. Perform LOAD TEST after repair.
5. Start engine and run at 2000 RPM with headlights on. Measure voltage at "B+" terminal of alternator and at alternator feed wire at starter relay. If voltage readings differ by more than 0.5 volt, repair high resistance or open in wire between "B+" terminal and junction near starter relay.
6. If alternator still does not charge sufficiently, connect a jumper wire from regulator "F" terminal screw and ground it to rear housing. If output voltage increases to 13-15 volts, replace regulator. If output voltage does not increase to at least 13 volts replace alternator.

"S" & "I" CIRCUIT TEST

1. Unplug regulator 3-wire harness connector. Connect jumper wire from harness "A" terminal to regulator "A" terminal. (Scheme 1)and (Scheme 2). Connect another jumper wire from regulator "F" terminal screw to alternator housing.
2. With engine idling, connect voltmeter negative lead to battery ground terminal. Connect voltmeter positive lead first to "S" terminal and then to "I" terminal of regulator harness connector. (Scheme 2) Voltage at "S" terminal should be about 7 volts and about 14 volts at "I" terminal. If "S" terminal and "I" voltages are okay, replace voltage regulator. Repeat LOAD TEST. If "S" and "I" circuit voltages are not as specified, go to next step.
3. If voltage is present at "S" terminal but not between 6-8 volts, replace alternator. If no voltage is present at "S" terminal, disconnect one-wire connector ("S" terminal) on back of alternator. (Scheme 1) Check voltage at single "S" terminal. If approximately 7 volts are present repair "S" circuit wiring. If no voltage is present at single "S" terminal, replace alternator.
4. If no voltage is present at "I" terminal, repair indicator light wiring circuit. Restore wiring connections and repeat LOAD TEST.

Scheme 2

FIELD CIRCUIT DRAIN TEST

Note. Connect voltmeter negative lead to alternator rear housing for following voltage readings.

1. Turn ignition switch to OFF position. Connect voltmeter positive lead to regulator "F" terminal screw. Battery voltage should be present.
2. If less than battery voltage is present, unplug regulator harness connector. Connect voltmeter positive lead to harness connector "I" terminal. (Scheme 2) If voltage is not present, go to next step. If voltage is present, repair wiring circuit "I" from ignition switch to eliminate voltage source.
3. Connect voltmeter positive lead to regulator wiring plug "S" terminal. If voltage is not present, replace regulator. If voltage is present, unplug alternator wiring connector.
4. Connect voltmeter positive lead to regulator wiring plug "S" terminal. If voltage is present, repair "S" terminal wiring circuit to alternator. If no voltage is present, replace alternator.

TROUBLE SHOOTING

Note. See the TROUBLE SHOOTING - BASIC PROCEDURES article in the GENERAL TROUBLE SHOOTING section.

REMOVAL & INSTALLATION

Disconnect negative battery cable. Disengage drive belt from pulley. Disconnect wiring from alternator. Remove alternator mounting bolts (and mounting bracket if necessary). Remove alternator. To install, reverse removal procedure.

1. Remove alternator. Remove 4 TORX(R) screws from regulator and separate regulator and brush holder from alternator.
2. Holding regulator in one hand, pry off the cap covering "A" terminal screw head with a screwdriver. Remove 2 screws attaching regulator to brush holder ("A" and "F" terminal screws). (Scheme 3) Separate regulator from brush holder. To install, reverse removal procedure. Tighten screws to 25-35 INCH lbs. (2.8-4.0 Nm.).

Scheme 3

OVERHAUL

Overhaul information is not supplied by manufacturer. The only serviceable parts are the integral voltage regulator and brush holder. (Scheme 3)

Charging System Wiring Diagram. Scheme 4

See also:
• COMPUTER RELEARN PROCEDURES
• TROUBLE SHOOTING - BASIC PROCEDURES