2003 FORD MUSTANG key battery

Pinpoint Tests
CAUTION: Before removing and installing the GEM or its connectors, disconnect the
battery. Failure to follow this caution will result in the GEM storing many erroneous DTCs and it
may exhibit erratic operation after installation.
CAUTION: Be careful when probing the central junction box (CJB), battery junction box
(BJB) or any connectors. Damage will result to the connector receptacle if the probe being
used is too large.
CAUTION: Electronic modules are sensitive to static electrical charges. If exposed to
these charges, damage may result.
NOTE: If continuous DTCs are recorded and the symptom is not present when carrying out the
pinpoint tests, an intermittent concern may be the cause. Always check for loose connections and
corroded terminals.
NOTE: Complete the entire pinpoint test related to the symptom before installing a new GEM.
PINPOINT TEST A: NO COMMUNICATION WITH THE GENERIC
ELECTRONIC MODULE (GEM) Test Step Result / Action to Take
CAUTION: Use the correct probe adapter(s) when making measurements. Failure to
use the correct probe adapter(s) may damage the connector. A1 CHECK THE GENERIC ELECTRONIC MODULE (GEM)
POWER SUPPLY z
Key in OFF position.
z Disconnect: Generic Electronic Module (GEM) C201a.
z Disconnect: GEM C201b.
z Key in ON position.
z Using the following table. measure the voltage between the
GEM, harness side and ground.
z Are the voltages greater than 10 volts? Connector Pin Circuit
C201a 4 400 (LB/BK)
C201a 1 1006 (DG/WH)
C201b 2 1001 (WH/YE)
C201b 3 193 (YE/LG) Yes
GO to
A2 .
No
REPAIR the circuit(s) in
question. TEST the system
for normal operation. A2 CHECK THE GEM GROUND CIRCUIT 397 (BK/WH) FOR
OPEN z
Key in OFF position.
z Measure the resistance between the GEM C201b pin 4,
circuit 397 (BK/WH), harness side and ground. Yes
GO to
A3 .
No
REPAIR the cirucit(s) in
question. TEST the system Klj . 6 ba
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No
GO to
B10 .
B4 TEST THE GEM CONTROL OF WIPER HIGH/LOW RELAY
z
Trigger the GEM active command WIPER RLY to ON.
z Trigger the GEM active command SPEED RLY ON and
OFF.
z Does wiper speed change on activation and
deactivation of SPEED RLY command? Yes
GO to
B5 .
No
GO to B16 .
B5 DETERMINE IF GEM IS RECEIVING CORRECT WIPER
POSITION STATUS z
Monitor GEM PID WPPRKSW while turning the wipers ON
using the multifunction switch.
z Do the PID values agree with the wiper position? Yes
INSTALL a new GEM. For
additional information,
REFER to
Section 419 - 10 .
CLEAR the DTCs. REPEAT
the self- test.
No
GO to B27 .
B6 TEST THE MULTIFUNCTION SWITCH FOR NORMAL
OPERATION z
Disconnect: Multifunction Switch C202a.
z Check the multifunction switch. Refer to Wiring Diagrams,
Cell 149, Component Testing.
z Is the multifunction switch OK? Yes
GO to
B7 .
No
INSTALL a new multifunction
switch; REFER to Section 211 - 05 . REPEAT the self-
test. CLEAR the DTCs. B7 CHECK CIRCUITS 682 (DB), 684 (PK/YE), AND 680
(LB/OG) FOR SHORT TO BATTERY BETWEEN THE GEM
AND THE MULTIFUNCTION SWITCH z
Disconnect: GEM C201e.
z Key in ON position.
z Using the following table, measure the voltage between
the GEM C201e Pins, harness side and ground.
z Are the voltages greater than 10 volts? Pin Circuit
5 682 (DB)
18 684 (PK/YE)
19 680 (LB/OG) Yes
REPAIR the circuit(s) in
question. REPEAT the self-
test. CLEAR the DTCs.
No
GO to
B8 .
B8 CHECK CIRCUITS 682 (DB), 684 (PK/YE), AND 680 Klj . 8 ba
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relay Pin 5, Circuit 65 (DG), harness side and ground; and
between BJB wiper ON/OFF relay Pin 2, Circuit 65 (DG),
harness side and ground.
z Are the voltages greater than 10 volts? REPAIR circuit(s) in question.
REPEAT the self-
test.
CLEAR the DTCs. B11 ISOLATE PROBLEM BETWEEN GEM AND BJB
z
Key in OFF position.
z Connect a fused jumper wire (30A) between wiper
ON/OFF relay Pin 3 and Pin 5, harness side.
z Key in ON position.
z Did the wiper motor activate? Yes
GO to
B12 .
No
GO to B22 .
B12 CARRY OUT THE WIPER ON/OFF RELAY COMPONENT
TEST z
Check the wiper ON and OFF relay; refer to Wiring
Diagrams, Cell 149, Component Testing.
z Is the ON/OFF wiper relay OK? Yes
GO to
B13 .
No
INSTALL a new wiper
ON/OFF relay. REPEAT the
self- test. CLEAR the DTCs. B13 CHECK CIRCUIT 646 (YE/WH) FOR SHORT TO
BATTERY BETWEEN GEM AND BJB z
Disconnect: Wiper On/Off Relay.
z Disconnect: GEM C201d.
z Measure the voltage between GEM C201d 3 Pin 12,
Circuit 646 (YE/WH), harness side and ground. Yes
REPAIR Circuit 646
(YE/WH). REPEAT the self-
test. CLEAR the DTCs.
No
GO to
B14 . Klj . 10 ba
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circuit 588 (VT), harness side.
z Is the resistance less than 5 ohms? Top Switch in this
section. TEST the
system for normal
operation.
No
REPAIR Circuit 588
(VT). TEST the
system for normal
operation. A6 CHECK CIRCUIT 688 (GY/LB) FOR OPEN
z
Key in OFF position.
z Disconnect: Convertible Top Switch C3115.
z Measure the resistance between convertible top switch C3115 pin
5, circuit 688 (GY/LB), harness side and lower relay C4064 pin 85,
circuit 688 (GY/LB), harness side.
z Is the resistance less than 5 ohms? Yes
INSTALL a new
convertible top switch.
REFER to
Convertible Top Switch in this
section. TEST the
system for normal
operation.
No
REPAIR circuit 688
(GY/LB). TEST the
system for normal
operation. A7 CHECK THE BATTERY SUPPLY TO THE RELAYS
z
Measure the voltage between raise relay C4063 pin 87, circuit 170
(RD/LB), harness side and ground; and between lower relay
C4064 pin 87, circuit 170 (RD/LB), harness side and ground.
z Are the voltages greater than 10 volts? Yes
GO to
A8 .
No
REPAIR circuit 170
(RD/LB). TEST the
system for normal
operation. A8 CHECK CIRCUIT 1205 (BK) FOR AN OPEN
z
Key in OFF position.
z Measure the resistance between raise relay C4063 pin 87A,
circuit 1205 (BK), harness side and ground; and between lower
relay C4064 pin 87A, circuit 1205 (BK), harness side and ground. Yes
GO to
A9 .
No
REPAIR the circuit.
TEST the system for
normal operation. Klj . 4 ba
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Pinpoint Test E: LFC 15/DTC B1916 —
Driver Air Bag Circuit Shorted to Battery or Ignition
Normal Operation
The restraints control module (RCM) checks for driver air bag circuit shorts to battery or ignition by
monitoring the voltage of circuit 614 (GY/OG) and 615 (GY/WH) at pins 3 and 4. If the RCM detects a
short to battery or ignition on either of these pins, it will store a diagnostic trouble code (DTC) B1916 in
memory and flash a lamp fault code (LFC) 15 (or higher priority code if one exists) on the air bag
indicator.
Possible Causes D5 CHECK FOR AN INTERMITTENT FAULT
z
Refer to the continuous DTCs recorded during Step D1.
z Was the continuous DTC retrieved during Step D1 an
intermittent fault? Yes
CHECK for causes
of intermittent short
to ground on circuit
614 (GY/OG),
circuit 615
(GY/WH), and the
clockspring
assembly. Attempt
to recreate the hard
fault by flexing the
wire harness and
cycling the ignition
key frequently.
REPAIR any
intermittent
concerns found.
GO to
D6 .
No
GO to D6 .
D6 CHECK FOR ADDITIONAL DTCs
z
Refer to continuous DTCs recorded during Step D1.
z Were any continuous DTCs retrieved during Step D1? Yes
Do not clear any
DTCs until all DTCs
have been
resolved. GO to the
Restraints Control
Module (RCM)
Diagnostic Trouble
Code (DTC) Priority
Table in this section
for pinpoint test
direction.
No
RECONNECT the
system.
REACTIVATE the
system. PROVE
OUT the system.
REFER to
Air Bag Supplemental
Restraint System
(SRS) in this
section. CLEAR all
DTCs. Klj . 12 ba
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A driver air bag circuit short to battery or ignition can be caused by:
za short to battery or ignition on circuit 614 (GY/OG).
z a short to battery or ignition on circuit 615 (GY/WH).
z a short to battery or ignition on the clockspring.
z a short to battery or ignition on the driver air bag module.
z an RCM internal concern.
PINPOINT TEST E: LFC 15/DTC B1916 — DRIVER AIR BAG CIRCUIT
SHORTED TO BATTERY OR IGNITION Test Step Result / Action to
Take E1 CHECK FOR A HARD OR INTERMITTENT DTC
z
Key in OFF position.
z Connect the diagnostic tool. Scan Tool
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic tool:
Retrieve/Clear Continuous DTCs.
z Retrieve and record any continuous DTCs for use later in this
pinpoint test.
z Enter the following diagnostic mode on the diagnostic tool: On-
Demand Self Test.
z Was DTC B1916 retrieved during the on- demand self test? Yes
This is a hard fault.
The fault condition
is still present. This
fault cannot be
cleared until it is
corrected and the
DTC is no longer
retrieved during the
on-
demand self
test. GO to E2 .
No
This in an
intermittent fault.
The fault condition
is not present at this
time. GO to E5 .
E2 CHECK THE DRIVER AIR BAG MODULE
WARNING: If the supplemental restraint system (SRS) is
being serviced, the system must be deactivated and restraint
system diagnostic tools must be installed. Refer to Air Bag Supplemental Restraint System (SRS) in this section.
The air bag restraint system diagnostic tools must be removed
and the air bag modules reconnected when the system is
reactivated to avoid non- deployment in a collision, resulting in
possible personal injury. NOTE: Diagnostics or repairs are not to
be performed on a seat equipped with a seat side air bag with the
seat in the vehicle. Prior to attempting to diagnose or repair a seat
concern when equipped with a seat side air bag, the seat must be
removed from the vehicle and the restraint system diagnostic tools
must be installed in the seat side air bag electrical connectors. The
restraint system diagnostic tools must be removed prior to
operating the vehicle over the road. NOTE: After diagnosing or
repairing an SRS, the restraint system diagnostic tools must be
removed before operating the vehicle over the road. NOTE:
After diagnosing or repairing a seat system, the restraint system
diagnostic tools must be removed before operating the vehicle Yes
GO to
E3 .
No
INSTALL a new
driver air bag
module. GO to E6 . Klj . 13 ba
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over the road. NOTE:
The SRS must be fully operational and free
of faults before releasing the vehicle to the customer.
z Key in OFF position.
z Deactivate the system. Refer to Air Bag Supplemental Restraint System (SRS) in the Diagnosis and Testing portion of this section.
z Key in OFF position.
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic tool: On-
Demand Self Test.
z Was DTC B1916 retrieved? E3 CHECK THE DRIVER AIR BAG MODULE CIRCUIT
z
Key in OFF position.
z Disconnect: Driver Air Bag Module Restraint System Diagnostic
Tool.
z Disconnect: RCM C2041.
z Key in ON position.
z NOTE: Do not separate or remove shorting bars from RCM C2041.
z Measure the voltage between RCM C2041 pin 3, circuit 614
(GY/OG), harness side and ground; and between RCM C2041 pin 4,
circuit 615 (GY/WH), harness side.
z Are the voltages less than 0.2 volt? Yes
INSTALL a new
RCM. GO to
E6 .
No
GO to E4 .
E4 CHECK THE DRIVER AIR BAG MODULE WIRING AND THE
CLOCKSPRING z
Disconnect: Clockspring C218b.
z Inspect all crimps, terminals, wires and connectors in circuit 614
(GY/OG) feeding the RCM pin 3, circuit 615 (GY/WH) feeding pin 4,
and the clockspring C218b. Check for pinched wires and damaged
connector pin terminals.
z Was any damage found? Yes
REPAIR as
necessary. GO to
E6
.
No
GO to E6 .
E5 CHECK FOR AN INTERMITTENT FAULT
z
Refer to the continuous DTCs recorded during Step E1.
z Was the continuous DTC retrieved during Step E1 an
intermittent fault? Yes
CHECK for causes
of intermittent short
to battery or ignition
on circuit 614
(GY/OG), circuit
615 (GY/WH), and
the clockspring
assembly. Attempt
to recreate the hard
fault by flexing the
wire harness and
cycling the ignition
key frequently.
REPAIR any
intermittent
concerns found. GO Klj . 14 ba
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Pinpoint Test G: LFC 16/DTC B1925 —
Passenger Air Bag Circuit Shorted to Battery or Ignition
Normal Operation
The restraints control module (RCM) checks for passenger air bag circuit shorts to battery or ignition
by monitoring the voltage of circuits 607 (LB/OG) and 616 (PK/BK) at pins 6 and 7. If the RCM detects
a short to battery or ignition on either of these pins, it will store a diagnostic trouble code (DTC) B1925
in memory and flash a lamp fault code (LFC) 16 (or higher priority code if one exists) on the air bag
indicator.
Possible Causes
A passenger air bag circuit short to battery or ignition can be caused by:
za short to battery or ignition on circuit 607 (LB/OG).
z a short to battery or ignition on circuit 616 (PK/BK).
z a short to battery or ignition on the passenger air bag module.
z an RCM internal concern.
PINPOINT TEST G: LFC 16/DTC B1925 — PASSENGER AIR BAG
CIRCUIT SHORTED TO BATTERY OR IGNITION REACTIVATE the
system. PROVE
OUT the system.
REFER to
Air Bag Supplemental
Restraint System
(SRS) in this
section. CLEAR all
DTCs. Test Step Result / Action to
Take G1 CHECK FOR A HARD OR INTERMITTENT DTC
z
Key in OFF position.
z Connect the diagnostic tool. Scan Tool
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic tool:
Retrieve/Clear Continuous DTCs.
z Retrieve and record any continuous DTCs for use later in this
pinpoint test.
z Enter the following diagnostic mode on the diagnostic tool: On-
Demand Self Test.
z Was DTC B1925 retrieved during the on- demand self test? Yes
This is a hard fault.
The fault condition
is still present. This
fault cannot be
cleared until it is
corrected and the
DTC is no longer
retrieved during the
on-
demand self
test. GO to G2 .
No
This is an
intermittent fault.
The fault condition
is not present at
this time. GO to
G5 . Klj . 18 ba
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