Mustang V8-302 5.0L HO (1987)
Charge Lamp/Indicator: Technical Service Bulletins
Charging System - Diagnostic Procedure Revision
Article No. 86-9-2
CHARGING SYSTEM DIAGNOSTIC PROCEDURE - REVISED
FORD 1986 TAURUS; 1987 MUSTANG
LINCOLN-MERCURY 1986 SABLE
LIGHT TRUCK 1986 AEROSTAR; 1987 F SERIES
The charging system function is now dependent on electrical continuity at the charge indicator light.
The charging system may become inoperative when any of the following conditions exist:
1.
The charging indicator bulb and socket assembly is not properly seated, or over-rotated within the socket hole during installation.
2.
The charging indicator bulb fails and the socket resistor is not present.
3.
The charging indicator bulb and socket assembly is not present.
The existing charging system procedures have been revised to cover the possibility of the three conditions described above (see 31-01-4).
Additional Corrections to Diagnostic Procedure (see 31-01-9)
Page 31-01-9 of the Taurus/Sable Shop Manual has been revised to correct the voltmeter lead callouts (polarities reversed), and Step 3 has been
reworked.
OTHER APPLICABLE ARTICLES: None
WARRANTY STATUS: "INFORMATION ONLY"
Indicator Lamp System
Normal Charge Indication The new integral Alternator Regulator (IAR) has a circuit in the regulator that will indicate a high battery voltage condition.
With the IAR system, three conditions can cause the charge indicator lamp to come on during vehicle operation:
1.
No alternator output: Damaged alternator, regulator or wiring.
2.
Over voltage correlation: Shorted alternator rotor, regulator or wiring.
With ignition switch in the OFF position:
Charge indicator battery symbol lamp is off. With ignition switch in the RUN position (engine not
running): Charge indicator (alternator) lamp is on. With ignition switch in the RUN position
(engine running): Charge indicator (alternator) lamp is off.
EVR System
1.
If charge indicator lamp does not come on with the ignition key in RUN position and engine not running, check the I wiring circuit (ignition switch
to regulator I terminal) for open circuit or burned out charge indicator lamp.
2.
If charge indicator lamp does not come on, disconnect wiring plug connector at regulator and connect a jumper wire from the I terminal of
regulator wiring plug to negative battery post cable clamp.
3.
Charge indicator lamp should go on with ignition key turned to RUN position.
4.
If charge indicator lamp does not go on, check for presence of bulb socket resistor. If resistor is missing, replace bulb socket. If resistor is present,
