F 250 4WD Super Duty V8-6.4L DSL Turbo (2008)
AC11-AC12
Tests AD: The Trailer Electric Brakes Are Inoperative/Do Not Operate Correctly
PINPOINT TEST AD: THE TRAILER ELECTRIC BRAKES ARE INOPERATIVE/DO NOT OPERATE CORRECTLY
NOTE: This pinpoint test diagnoses the circuitry supplied for an aftermarket trailer electric brake controller. For diagnostics regarding the factory
trailer brake control system, refer to Towing / Trailer System.
Normal Operation
The trailer electric brake controller is provided voltage at all times by the battery junction box (BJB) fuse 5 (30A) through circuit SBB05 (GY/RD).
Ground for the trailer electric brake controller is provided through circuit GD115 (BK/GY). The trailer electric brake controller receives voltage from
the stoplamp switch through circuit CLS43 (YE/GN) when the brake pedal is applied. When a brake application is detected from the stoplamp switch,
the trailer electric brake controller sends voltage to the trailer tow connector through circuit CAT19 (BU).
This pinpoint test is intended to diagnose the following:
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Fuse
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Wiring, terminals or connectors
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Trailer tow connector
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Trailer electric brake controller
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Trailer