1996 Bronco/F-Series

Section 17-02: Lighting, Interior

1996 F-150, F-250, F-350, F-Super Duty Chassis Cab and Bronco Vehicles Workshop Manual

DIAGNOSIS AND TESTING

Pinpoint Tests — Courtesy Lamps

PINPOINT TEST A: COURTESY LAMPS INOPERATIVE

A1 CHECK INTERIOR LAMPS FUSE 8 (15A) FOR VOLTAGE

Using Rotunda 73 Digital Multimeter 105-R0051 or equivalent, check voltage at IP fuse 8 (15A) for voltage.

Is voltage present?

Yes	No
SERVICE open in Circuit 54 (LG/Y) RESTORE vehicle. RETEST system.	GO to A2.

A2 CHECK CIRCUIT 54 (LG/Y) FOR SHORT

Remove IP fuse 8 (15A).
Connect one lead of ohmmeter to a known good ground, connect second lead to output side of IP fuse 8 (15A). Measure resistance.

Is resistance 5 ohms or less?

Yes	No
SERVICE Circuit 54 (LG/Y) for short to ground. RESTORE vehicle. REPLACE IP fuse 8 (15A). RETEST system.	REPLACE IP fuse 8 (15A). RETEST system.

PINPOINT TEST B: COURTESY LAMPS ON CONTINUOUSLY

B1 CHECK HEADLAMP SWITCH

With all doors closed, remove the connector from the headlamp switch.

Do courtesy lamps go out?

Yes	No
REPLACE headlamp switch. RESTORE vehicle. RETEST system.	GO to B2.

B2 CHECK COURTESY LAMP SWITCHES

Close the doors.
Disconnect courtesy lamp switches one at a time.

Do courtesy lamps go out when any courtesy lamp switch is disconnected?

Yes	No
REPLACE shorted courtesy lamp switch. RESTORE vehicle. RETEST system.	SERVICE battery short in Circuit 53 (BK/LB) or Circuit 55 (BK/PK). RESTORE vehicle. RETEST system.

PINPOINT TEST C: DOME LAMP INOPERATIVE

C1 HEADLAMP SWITCH CHECK DOME LIGHT ON

With the headlamp switch in the ON position for the dome light, use a volt-ohmmeter to check for voltage at terminal D2 of the headlamp switch.

Is voltage present at Pin D2?

Yes	No
GO to C2.	REPLACE headlamp switch. RESTORE vehicle. RETEST system.

C2 CHECK CIRCUIT 53 (BK/LB)

Disconnect dome lamp.
With headlamp switch in the ON position for dome light activation, use a volt-ohmmeter to check Circuit 53 (BK/LB) at the dome light for voltage.

Is voltage present?

Yes	No
GO to C3.	REPAIR open in Circuit 53 (BK/LB). RESTORE vehicle. RETEST system.

C3 CHECK DOME LAMP GROUND

With a volt-ohmmeter check the dome lamp ground side.

Is there resistance?

Yes	No
REPLACE dome lamp.	REPLACE dome lamp fixture. RESTORE vehicle. RETEST system.

PINPOINT TEST D: ONE OR MORE MAP LAMPS INOPERATIVE

D1 CHECK POWER TO MAP LAMPS

Gain access to Circuit 705 (LG/O) at the map lamp fixture.
Using a volt-ohmmeter, check for battery voltage in Circuit 705 (LG/O) at the map lamps.

Is battery voltage present?

Yes	No
GO to D2.	SERVICE Circuit 54 (LG/Y) or Circuit 705 (LG/O) for open or ground short. RESTORE vehicle. RETEST system.

D2 CHECK MAP LAMP SWITCHES

Remove the miniature bulbs from the map lamp fixture.
Using a volt-ohmmeter and with the map lamp switch in the ON position, check for battery voltage at each of the map lamps.

Is voltage present?

Yes	No
GO to D3.	REPLACE damaged switch. RESTORE vehicle. RETEST system.

D3 CHECK MAP LAMP GROUND

With a volt-ohmmeter, check the ground side of the map lamp fixture.

Is continuity present?

Yes	No
REPLACE miniature bulb. RESTORE vehicle. RETEST system.	SERVICE map lamp ground. RESTORE vehicle. RETEST system.

PINPOINT TEST E: ENGINE COMPARTMENT LAMP INOPERATIVE

E1 CHECK ENGINE COMPARTMENT LAMP SUPPLY

Remove compartment lamp. Refer to Lamp, Engine Compartment in the Removal and Installation portion of this section.
Using a voltmeter, check Circuit 54 (LG/Y) for voltage.

Is voltage present?

Yes	No
GO to E2.	SERVICE Circuit 54 (LG/Y) or Circuit 705 (LG/O) for open or ground short. RESTORE vehicle. RETEST system.

E2 CHECK ENGINE COMPARTMENT LAMP GROUND

Using an ohmmeter connected to a known good ground, check continuity between Circuit 57 (BK) at compartment lamp and known good ground.

Is continuity present?

Yes	No
GO to E3.	SERVICE Circuit 57 (BK) for open circuit. RESTORE vehicle. RETEST system.

E3 CHECK ENGINE COMPARTMENT LAMP BULB

Remove engine compartment lamp bulb.
Using an ohmmeter, check continuity of bulb.

Does bulb test OK?

Yes	No
REPLACE compartment lamp. RESTORE vehicle. RETEST system.	REPLACE engine compartment lamp miniature bulb. RESTORE vehicle. RETEST system.

PINPOINT TEST F: GLOVE COMPARTMENT LAMP INOPERATIVE

F1 CHECK GLOVE COMPARTMENT LAMP POWER SUPPLY

Disconnect glove compartment lamp connector.
Using a volt-ohmmeter, check Circuit 54 (LG/Y), without remote keyless entry or Circuit 705 (LG/O) with remote keyless entry, for battery voltage.

Is voltage present?

Yes	No
GO to F2.	SERVICE Circuit 54 (LG/Y) or Circuit 705 (LG/O) for open or ground short. RESTORE vehicle. RETEST system.

F2 SWITCH CHECK

With glove compartment open (switch in ON position), remove the miniature bulb.
Check the power side of the lamp fixture for voltage.

Is voltage present?

Yes	No
GO to F3.	REPLACE the glove compartment lamp fixture. RESTORE vehicle. RETEST system.

F3 GROUND SIDE TEST

Using a volt-ohmmeter, check the ground side of the glove compartment lamp assembly.

Is continuity present?

Yes	No
REPLACE miniature bulb. RESTORE vehicle. RETEST system.	SERVICE glove compartment lamp fixture ground. RESTORE vehicle. RETEST system.

PINPOINT TEST G: GLOVE COMPARTMENT LAMP ON CONTINUOUSLY

G1 GLOVE COMPARTMENT SWITCH CHECK

Remove the miniature bulb.
Place the glove compartment switch in the OFF position.
Using a volt-ohmmeter, check to see if there is voltage on the power side of the glove compartment lamp fixture for voltage.

Is voltage present?

Yes	No
REPLACE the glove compartment lamp fixture. RESTORE vehicle. RETEST system.	System OK.

PINPOINT TEST H: VANITY MIRROR LAMPS INOPERATIVE

H1 CHECK VANITY MIRROR LAMPS SUPPLY

Remove vanity mirror lamp assembly.
Disconnect vanity mirror.
Using a voltmeter, check Circuit 54 (LG/Y), without remote keyless entry or Circuit 54 (LG/Y) and Circuit 705 (LG/O) with remote keyless entry, for voltage.

Is voltage present?

Yes	No
GO to H2.	SERVICE Circuit 54 (LG/Y) or Circuit 705 (LG/O) for open or ground short. RESTORE vehicle. RETEST system.

H2 CHECK VANITY MIRROR LAMPS GROUND

Remove vanity mirror lamp bulb.
Using an ohmmeter connected to a known good ground, check ground side of bulb socket for continuity.

Is continuity present?

Yes	No
GO to H3.	SERVICE open ground circuit. RESTORE vehicle. RETEST system.

H3 CHECK VANITY MIRROR LAMP BULB

Using an ohmmeter, check continuity of bulb.

Is continuity present?

Yes	No
REPLACE vanity mirror assembly. RESTORE vehicle. RETEST system.	REPLACE vanity mirror lamp bulb. RESTORE vehicle. RETEST system.

PINPOINT TEST J: VANITY MIRROR LAMPS ON CONTINUOUSLY

J1 VANITY MIRROR LAMPS ON CONTINUOUSLY

Disconnect Circuit 54 (LG/Y) to affect vanity mirror.
With the switch in the OFF position and using a volt-ohmmeter, check continuity from Circuit 54 (LG/Y) to the output side of the switch.

Is continuity present?

Yes	No
SERVICE the vanity mirror switch. RESTORE vehicle. RETEST system.	System OK.