2003 FORD MUSTANG Workshop Manual

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FORD MUSTANG 2003  Workshop Manual DIAGNOSIS AND TESTING 
Daytime Running Lamps (DRL) 
Refer to Wiring Diagrams Cell 
97  , Daytime Running Lamps for schematic and connector information. 
Principles of Operation 
Daytime Running Lamps

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FORD MUSTANG 2003  Workshop Manual next step. For additional information, refer to 
Section 417 - 01  . 
4. Verify the parking brake control is fully released. 
5. If an obvious cause for an observed or reported concern is found, corre

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FORD MUSTANG 2003  Workshop Manual �z
Is the resistance greater than 10,000 ohms?  A2 CHECK THE PARKING BRAKE SWITCH 
�z
Disconnect: Parking Brake Switch C306. 
�z Measure the resistance between DRL module C1030 Pin 
6, Circuit 22 (LB/

Page 3516 of 4378

FORD MUSTANG 2003  Workshop Manual PINPOINT TEST B: THE DAYTIME RUNNING LAMPS ARE ON WITH 
THE PARKING BRAKE SET  �z
Is the voltage greater than 10 volts?  A5 CHECK THE DRL MODULE GROUND —
CIRCUIT 1205 
(BK)  �z
Measure the resistanc

Page 3517 of 4378

FORD MUSTANG 2003  Workshop Manual PINPOINT TEST C: THE DAYTIME RUNNING LAMPS ARE ON WITH 
THE IGNITION SWITCH OFF  �z
Do the DRL turn off?  B2 CHECK THE PARKING BRAKE SWITCH SIGNAL CIRCUIT 
�z
Key in OFF position. 
�z Disconnect: DRL

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FORD MUSTANG 2003  Workshop Manual PINPOINT TEST D: THE LOW BEAM HEADLAMPS ARE ON AT FULL 
INTENSITY IN DRL MODE 
Test Step  Result / Action to Take 
D1 CHECK THE LOW BEAM 
HEADLAMPS INPUT  �z
Disconnect: DRL Module 
C1030. 
�z Are the

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FORD MUSTANG 2003  Workshop Manual REMOVAL AND INSTALLATION 
Module —
Daytime Running Lamps (DRL) 
Removal 
1.  CAUTION: Electronic modules are sensitive to static electrical charges. If exposed 
to these charges, damage can result.

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FORD MUSTANG 2003  Workshop Manual Klj .  2 ba
  22003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...