yo N,
WELCOME!
In this diagram, Brown wire is for Headlamps on with the key in the ignition switch lock cylinder
I believe you can terminate it, but chime won't ding, My eyesight is off a bit again, so maybe someone else can help you with the diagrams.
The warning chime/buzzer sounds when the headlamp switch (11654) is in PARK or HEAD and the driver's door is open, and continues to sound until the headlamp switch is moved to OFF or the door is closed. When the headlamp switch is in PARK or HEAD, power is supplied through Circuit 14 (BR) to the module. When the driver's door is open, the driver's door lamp switch (13713) is closed and power is supplied to the module through Circuit 159 (R/PK).
here is the 1996 Bronco/F-Series Workshop Manual
https://www.motorcraftservice.com/pubs/content/~WSTJ/~MUS~LEN/21/STJLEFT.HTM
Section 13-09: Gauges/Warning Devices, Chime/Buzzer System
1996 Bronco/F-Series Workshop Manual
DESCRIPTION AND OPERATION
Procedure revision date: 05/18/200
Key-in-Ignition Warning
The warning chime/buzzer sounds when the driver's door is open with the key in the ignition switch lock cylinder (11582), and continues to sound until the key is removed or the door is closed. When the key is in the ignition switch lock cylinder, the key-in-ignition switch is closed and ground is supplied to the warning chime/buzzer module through Circuit 158 (BK/PK). When the driver's door is open, the driver's door lamp switch (13713) is closed and power is supplied to the module through Circuit 159 (R/PK).
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Warning Chime/Buzzer System
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PINPOINT TEST C: KEY-IN-IGNITION WARNING Inoperative
https://www.motorcraftservice.com/pubs/content/~WSTJ/~MUS~LEN/21/STJD9008.HTM
C1 CHECK KEY-IN-IGNITION INPUT
- Open driver door.
- Using a jumper wire connected to a known good ground, connect other end of jumper to Pin 4, Circuit 158 (BK/PK) at warning chime/buzzer module connector.
Does warning chime/buzzer module sound?
Yes No GO to
C2 . GO to
C3 .
C2 CHECK CIRCUIT 158 (BK/PK) FOR OPEN
- Disconnect warning chime/buzzer module.
- Disconnect key-in-ignition switch at steering column.
- Using an ohmmeter, connect one lead to Pin 4, Circuit 158 (BK/PK) at warning chime/buzzer module connector. Connect second lead to Circuit 158 (BK/PK) at key-in-ignition switch connector.
- Check for continuity.
Is continuity present?
Yes No REPLACE key-in-ignition switch. RESTORE vehicle. RETEST system. SERVICE Circuit 158 (BK/PK) for open. RESTORE vehicle. RETEST system.
11-05: Steering Column Switches
1996 Bronco/F-Series Workshop Manual
DIAGNOSIS AND TESTING
Procedure revision date: 05/18/2000
Electrical Schematics
Ignition Switch
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Ignition Switch Continuity Test
NOTE: For an engine-won't-crank condition with an automatic transmission (7003), determine if the condition exists with the shift control selector level in both PARK and NEUTRAL positions before performing the ignition switch continuity tests. If the no-crank condition occurs in one shift lever position but not the other, a more probable cause is the neutral start switch located in the transmission.
Disconnect ignition key warning switch terminal and wire from the ignition switch (11572). Test the continuity of the ignition switch as described in the following illustrations. Connect a self-powered test lamp or ohmmeter between the blade terminals indicated on the chart. No continuity between any blade and chassis ground should exist in any ignition switch position except the proof Circuit 41 (BK/LB) (Pin P1) and Circuit 512 (T/LG) (Pin P2) in the START position only.
Ignition Switch, F-Series and Bronco
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