Ford 2003 Mustang Workshop Manual page 824

Circuit Failure
B2488 RF Side Repeater Lamp Output
Circuit Failure
C1189 Brake Fluid Level Sensor Input
Short Circuit to Ground
C1223 Lamp Brake Warning Output
Circuit Failure
C1225 Lamp Brake Warning Output
Circuit Short to Battery
Symptom Chart
Symptom Chart
Condition
No communication with
the generic electronic
module
The ignition switch is
inoperative
No power in ACC
No power in RUN
No power in START
The multifunction
switch/hazard switch
does not operate
correctly
Pinpoint Tests
PINPOINT TEST A: NO COMMUNICATION WITH THE GENERIC
ELECTRONIC MODULE
CAUTION: Use the correct probe adapter(s) when making measurements. Filaure to
use the correct probe adapter(s) may damage the connector.
A1 CHECK THE GENERIC ELECTRONIC MODULE (GEM)
POWER SUPPLY
Key in OFF position.
Disconnect: Generic Electronic Module (GEM) C201a.
GEM
GEM
GEM
GEM
Possible Sources
CJB Fuse 39
(5A).
Circuitry.
GEM.
BJB Fuse IGN
SW (40A).
Ignition switch.
Circuitry.
Ignition switch.
Circuitry.
Ignition switch.
Circuitry.
Ignition switch.
Circuitry.
Multifunction
switch.
Test Step
REFER to Section 417-01
REFER to Section 413-01
REFER to Section 413-01
REFER to Section 413-01
Action
Go To Pinpoint Test A .
Go To Pinpoint Test B .
Go To Pinpoint Test C
Go To Pinpoint Test D
Go To Pinpoint Test E .
Carry out the multifunction
switch component test.
REFER to Wiring Diagrams,
Cell 149, Component
Testing.
Result / Action to Take
Yes
GO to A2 .
.
.
.
.
.
.