key battery FORD MUSTANG 2003 User Guide

z
check the connections to the vehicle.
z check the ignition switch position.
4. If the scan tool still does not communicate with the vehicle, refer to the scan tool manual.
5. Carry out the DATA LINK DIAGNOSTIC TEST. If the scan tool responds with: zCKT914, CKT915 or CKT70 =ALL ECUS NO RESP/NOT EQUIP, refer to Section 418 -
00 .
z NO RESP/NOT EQUIP for GEM, go to Pinpoint Test A.
z SYSTEM PASSED, retrieve and record the continuous diagnostic trouble codes (DTCs),
erase the continuous DTCs and carry out self- test diagnostics for the GEM.
6. If the DTCs retrieved are related to the concern, go to the GEM Diagnostic Trouble Code (DTC) Index to continue diagnostics.
7. If no DTCs related to the concern are retrieved, proceed to the Symptom Chart to continue diagnostics.
GEM Diagnostic Trouble Code (DTC) Index GEM Diagnostic Trouble Code (DTC) Index DTC Description Source Action
B1217 Horn Relay Coil Circuit Failure GEM REFER to
Section 413 - 06 .
B1218 Horn Relay Coil Circuit Short to
Vbatt GEM REFER to
Section 413 - 06 .
B1312 Lamp Headlamp Input Circuit
Short to Battery GEM REFER to
Section 417 - 01 .
B1317 Battery Voltage High GEM REFER to
Section 414 - 00 .
B1318 Battery Voltage Low GEM REFER to
Section 414 - 00 .
B1322 Driver Door Ajar Circuit Short to
Ground GEM REFER to
Section 417 - 02 .
B1330 Passenger Door Ajar Circuit
Short to Ground GEM REFER to
Section 417 - 02 .
B1334 Decklid Ajar Rear Door Circuit
Short to Ground GEM REFER to
Section 417 - 02 .
B1339 Chime Input Request Circuit
Short to Battery GEM REFER to
Section 413 - 09 .
B1340 Chime Input Request Circuit
Short to Ground GEM REFER to
Section 413 - 09 .
B1342 ECU Is Defective GEM CLEAR the DTC. Retrieve the DTCs. If DTC
B1342 is retrieved, INSTALL a new GEM. REFER to Section 419 - 10 .
B1353 Ignition Key-
In Circuit Open GEM REFER to
Section 413 - 09 .
B1359 Ignition Run/Acc Circuit Failure GEM GO to
Pinpoint Test E .
B1396 Power Door Lock Circuit Short
to Battery GEM REFER to
Section 501 - 14B .
B1397 Power Door Unlock Circuit
Short to Battery GEM REFER to
Section 501 - 14B . Klj . 2 ba
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Symptom Chart
Pinpoint Tests
PINPOINT TEST A: NO COMMUNICATION WITH THE GENERIC
ELECTRONIC MODULE Circuit Failure
B2488 RF Side Repeater Lamp Output
Circuit Failure GEM REFER to
Section 417 - 01 .
C1189 Brake Fluid Level Sensor Input
Short Circuit to Ground GEM REFER to
Section 413 - 01 .
C1223 Lamp Brake Warning Output
Circuit Failure GEM REFER to
Section 413 - 01 .
C1225 Lamp Brake Warning Output
Circuit Short to Battery GEM REFER to
Section 413 - 01 .
Symptom Chart Condition
Possible Sources Action
z No communication with
the generic electronic
module z
CJB Fuse 39
(5A).
z Circuitry.
z GEM. z
Go To Pinpoint Test A .
z The ignition switch is
inoperative z
BJB Fuse IGN
SW (40A).
z Ignition switch.
z Circuitry. z
Go To Pinpoint Test B .
z No power in ACC zIgnition switch.
z Circuitry. z
Go To Pinpoint Test C .
z No power in RUN zIgnition switch.
z Circuitry. z
Go To Pinpoint Test D .
z No power in START zIgnition switch.
z Circuitry. z
Go To Pinpoint Test E .
z The multifunction
switch/hazard switch
does not operate
correctly z
Multifunction
switch. z
Carry out the multifunction
switch component test.
REFER to Wiring Diagrams,
Cell 149, Component
Testing. Test Step Result / Action to Take
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 z
Key in OFF position.
z Disconnect: Generic Electronic Module (GEM) C201a. Yes
GO to
A2 . Klj . 4 ba
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REMOVAL AND INSTALLATION
Multifunction Switch
Removal
1. Disconnect the battery ground cable.
2. Remove the ignition switch lock cylinder. 1. Insert the ignition key into the ignition switch lock cylinder and turn to RUN position.
2. Push the ignition switch lock cylinder release tab with a punch while pulling out the ignition switch lock cylinder.
3. Remove the tilt wheel handle.
4. Remove the upper and lower steering column shrouds. 1. Remove the screws.
2. Remove the upper and lower steering column shrouds.
5. Remove the multifunction switch. 1. Remove the screws.
SECTION 211-
05: Steering Column Switches 2003 Mustang Workshop Manual Klj . 1 ba
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REMOVAL AND INSTALLATION
Key Release Button
Removal
1. Disconnect the battery ground cable.
2. Remove the ignition switch lock cylinder. 1. Insert the ignition key into the ignition switch lock cylinder and turn to RUN position.
2. Push the ignition switch lock cylinder release tab with a punch while pulling out the ignition switch lock cylinder.
3. Remove the tilt wheel handle.
4. Remove the upper and lower steering column shrouds. 1. Remove the screws.
2. Remove the upper and lower steering column shrouds.
5. Remove the key release button. 1. Remove the key release button bolt.
SECTION 211-
05: Steering Column Switches 2003 Mustang Workshop Manual Klj . 1 ba
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PINPOINT TEST C: THE ENGINE CRANKS SLOWLY
PINPOINT TEST D: UNUSUAL STARTER NOISE z
Measure the resistance between the starter motor relay pin 86,
circuit 1205 (BK) and ground.
z Is the resistance less than 5 ohms? Test Step Result / Action to Take
NOTE:
Before beginning this test, be sure that the battery is tested and fully charged. C1 CHECK THE VOLTAGE TO THE STARTER
z
Key in OFF position.
z Measure the voltage between the starter motor
solenoid positive terminal and ground.
z Is the voltage 12.5 volts or greater? Yes
GO to
C2 .
No
REPAIR the circuit between the
battery and the starter solenoid.
CLEAN and TIGHTEN the
connections at the battery terminals.
TEST the system for normal
operation. C2 CHECK MOTOR GROUND CIRCUIT
z
Carry out the Motor Ground Circuit test; refer to
Component Tests in this section.
z Is the ground OK? Yes
INSTALL a new starter motor.
REFER to
Starter Motor — 3.8L or
Starter Motor — 4.6L . TEST the
system for normal operation.
No
REPAIR the ground circuit as
necessary. TEST the system for
normal operation. Test Step Result / Action to Take
D1 CHECK THE STARTER MOTOR
MOUNTING z
Inspect the starter motor mounting Yes Klj . 7 ba
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NOTE:
Refer to the Transmission Vehicle Harness Connector illustration preceding these
pinpoint tests. A1 ELECTRONIC DIAGNOSTICS
z
Select PARK.
z Key in OFF position.
z Check to make sure the transmission harness connector
is fully seated, pins are fully engaged in connector and
in good condition before proceeding.
z Connect the diagnostic tool.
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic
tool: Diagnostic Data Link.
z Enter the following diagnostic mode on the diagnostic
tool: PCM.
z Enter the following diagnostic mode on the diagnostic
tool: Active Command Modes.
z Enter the following diagnostic mode on the diagnostic
tool: Output State Control (OSC).
z Enter the following diagnostic mode on the diagnostic
tool: Trans- Bench Mode.
z Does vehicle enter Trans- Bench Mode? Yes
GO to
A2 .
No
REPEAT procedure to enter
Trans-Bench Mode. If vehicle
did not enter Trans- Bench
Mode, REFER to the Powertrain
Control/Emissions Diagnosis
(PC/ED) manual for diagnosis
of PCM. A2 WIGGLE TEST
z
Select PIDs to be monitored.
z Select "ON" to turn suspect solenoid on.
z Press "SEND".
z Wiggle all wiring and connectors to the transmission.
Monitor the Solenoid State for changes.
z Select "OFF" to turn solenoid off.
z Press "SEND".
z Does the suspect solenoid(s) fault state change? PID Command PID Actual
SSA SS1F
SSB SS2F
TCC TCCF Yes
REPAIR open or short in the
vehicle harness or connector.
No
GO to
A3 .
A3 SOLENOID FUNCTIONAL CHECK
z
Monitor each solenoid state.
z Turn each solenoid ON and OFF.
z Does the solenoid turn ON and OFF when
commanded and can solenoid activation be heard? Yes
GO to
A4 .
No
GO to A5 .
A4 OSC TRANS-
DRIVE MODE (GR_CM OR TCC) z
Carry out OSC Trans- Drive Mode.
z Select GR_CM for Shift Solenoids or follow procedures
for GR_CM as listed.
z Select TCC for Torque Converter Clutch Solenoid.
Follow procedures of TCC in Drive Mode as listed.
z Does the transmission upshift and downshift or
torque converter engage/disengage when
commanded? Yes
CLEAR all DTCs. ROAD TEST
to verify if concern is still
present. If concern is still
present, REFER to
Diagnosis By Symptom in this section to
diagnose shift or torque
converter concern.
No
GO to A5 .
A5 CHECK FOR BATTERY VOLTAGE
z
Remove transmission fluid pan. Yes Klj . 4 ba
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D2 SOLENOID FUNCTIONAL TEST
z
Install 2,060 kPa (300 psi) pressure gauge into EPC tap.
z Monitor pressure gauge.
z Enter the following diagnostic mode on the diagnostic tool:
Parameter; EPC.
z Select value - 15, 30, 45, 60, 70 or 90 psi.
z Press "SEND".
z Select another value "0- 90 psi".
z Press "SEND".
z Enter the following diagnostic mode on the diagnostic tool:
XXX.
z Press "SEND".
z Does the pressure reading match the commanded
pressure? Yes
CLEAR DTCs. REPEAT OBD
Tests.
No
GO to
D3 .
D3 CHECK FOR BATTERY VOLTAGE
z
Remove transmission fluid pan.
z Visually inspect the lead frame connectors for damage.
z Key in ON position.
z Measure the voltage with positive lead to VPWR solenoid
pin and negative lead to a good ground.
z Is voltage greater than 10 volts? Yes
GO to
D4 .
No
REPAIR the circuit. CLEAR
the DTCs. REPEAT the OBD
Tests. D4 ELECTRICAL SIGNAL CHECK
z
Measure the voltage with positive lead connected to
VPWR solenoid pin and connect negative lead to the
signal pin of the EPC solenoid.
z Turn the solenoids ON and OFF, while monitoring the
voltage reading, solenoid state on the scan tool (ON and
OFF), listen for the solenoid to activate (click).
z Enter the following diagnostic mode on the diagnostic tool:
Trans- Bench Mode.
z Enter the following diagnostic mode on the diagnostic tool:
Parameter EPC.
z Select a value "0- 90 psi".
z Press "SEND".
z Select another value "0- 90 psi".
z Press "SEND".
z Enter the following diagnostic mode on the diagnostic tool: Yes
GO to
D5 .
No
CHECK for open or short
circuit in harness or PCM. Klj . 18 ba
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PINPOINT TEST I: NO OPERATION IN HIGH BLOWER SETTING z
Is the resistance less than 5 ohms? Low None
Medium/low 2 and 3 only
Medium/high 2, 3 and 4 only
High 1, 2 and 4 only INSTALL a new heater blower
motor switch. REFER to
Section 412 - 04 . TEST the system for
normal operation. H4 CHECK THE FUNCTION SELECT SWITCH FOR A
SHORT TO BATTERY z
Key in OFF position.
z Disconnect: Function Selector Switch C294c.
z Key in ON position.
z Did the blower motor stop operating? Yes
INSTALL a new function selector
switch. REFER to
Section 412 -
04 . TEST the system for normal
operation.
No
REPAIR circuit 249 (DB/LG) for a
short to battery. TEST the system
for normal operation. Test Step Result / Action to Take
I1 CHECK CIRCUIT 261 (OG/BK) FOR AN OPEN CIRCUIT
z
Key in OFF position.
z Disconnect: Blower Motor Switch C294a.
z Key in ON position.
z Turn the function selector switch to the FLOOR position.
z Measure the voltage between blower motor switch C294a,
circuit 261 (OG/BK), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
I2 .
No
REPAIR circuit 261 (OG/BK)
for an open circuit. TEST the
system for normal operation. I2 CHECK CIRCUIT 1205 (BK) FOR AN OPEN Klj . 35 ba
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The boost pressure gauge on the instrument cluster receives and measures the boost pressure
directly from the intake manifold. The boost pressure gauge will display between 0.0-
0.48 kpa (0.0-10
psi) boost pressure dependent upon accelerator position, engine load, and engine rpm.
LOW FUEL Level Indicator
The low fuel level indicator is hardwired from the fuel sender to the instrument cluster. The instrument
cluster will illuminate the low fuel indicator when the usable fuel quantity is less than 1/8 tank (15%) of
fuel tank capacity.
Oil Pressure Gauge
The oil pressure gauge is hardwired from the oil pressure switch to the instrument cluster. The oil
pressure gauge will indicate either normal or no oil pressure.
CHECK FUEL CAP
The CHECK FUEL CAP indicator is used to indicate significant leaks in the fuel tank evaporative
system due to a loose fuel cap. Fuel tank pressure is monitored by the PCM. If a leak is detected the
PCM signals a fault to the instrument cluster via the SCP network. Once the PCM has detected a
loose fuel cap and the CHECK FUEL CAP indicator is illuminated, the indicator will remain illuminated
until the fuel cap is secured and the vehicle has been running for several minutes. For additional
information, refer to the Powertrain Control/Emissions Diagnosis (PC/ED) manual.
BRAKE Warning Indicator
The BRAKE warning indicator activates when the generic electronic module (GEM) detects the ignition
switch circuits are in the RUN state, when the GEM detects low brake fluid level, or that the parking
brake is applied. The BRAKE warning indicator will prove out starting when the GEM detects that the
ignition circuits have made a transition to RUN or START from OFF, ACC, or keyout and ending when
either three seconds have elapsed or when the GEM detects the ignition circuits have made a
transition to OFF, ACC, or keyout.
Safety Belt Warning Indicator
The safety belt switch is hardwired to the GEM. The safety belt warning indicator will be illuminated
when the GEM sends a ground signal to the instrument cluster.
ABS Warning Indicator
The ABS warning indicator will be illuminated when the anti- lock brake control module sends a ground
signal to the instrument cluster. The prove- out of the ABS indicator is controlled by the anti- lock brake
control module.
SERVICE ENGINE SOON Indicator
The SERVICE ENGINE SOON indicator receives its signal from the PCM over the SCP network. If the
instrument cluster does not receive a message from the PCM within five seconds, the instrument
cluster will illuminate the SERVICE ENGINE SOON indicator and log a diagnostic trouble code (DTC).
High Beam Indicator
The high beam indicator will illuminate when the steering column multifunction switch is in the high
beam position by sending a battery signal to the instrument cluster. Right and Left Turn Indicator Klj . 3 ba
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GEM Diagnostic Trouble Code (DTC) Index
DTC Description Source Action
B1218 Horn Relay Coil Circuit Short to
VBatt GEM REFER to
Section 501 - 14B .
B1312 Lamp Headlamp Input Circuit
Short to Battery GEM REFER to
Section 413 - 09 .
B1317 Battery Voltage High GEM REFER to
Section 414 - 00 .
B1318 Battery Voltage Low GEM REFER to
Section 414 - 00 .
B1322 Driver Door Ajar Circuit Short to
Ground GEM REFER to
Section 417 - 02 .
B1330 Passenger Door Ajar Circuit
Short to Ground GEM REFER to
Section 417 - 02 .
B1334 Decklid Ajar Rear Door Circuit
Short to Ground GEM REFER to
Section 417 - 02 .
B1339 Chime Input Request Circuit
Short to Battery GEM REFER to
Section 413 - 09 .
B1340 Chime Input Request Circuit
Short to Ground GEM REFER to
Section 413 - 09 .
B1342 ECU is Defective GEM Clear the DTCs. Retrieve the DTCs. If DTC B1342
is retrieved, INSTALL a new GEM. REFER to Section 419 - 10 .
B1353 Ignition Key-
In Circuit Open GEM REFER to
Section 413 - 09 .
B1359 Ignition Run/Acc Circuit Failure GEM REFER to
Section 211 - 05 .
B1396 Power Door Lock Circuit Short
to Battery GEM REFER to
Section 501 - 14B .
B1397 Power Door Unlock Circuit
Short to Battery GEM REFER to
Section 501 - 14B .
B1405 Driver Power Window Down
Circuit Short to Battery GEM REFER to
Section 501 - 11 .
B1408 Driver Power Window Up
Circuit Short to Battery GEM REFER to
Section 501 - 11 .
B1426 Lamp Safety Belt Circuit Short
to Battery GEM Go To Pinpoint Test K .
B1428 Lamp Safety Belt Circuit Failure GEM Go To Pinpoint Test K .
B1431 Wiper Brake/Run Relay Circuit
Failure GEM REFER to
Section 501 - 16 .
B1432 Wiper Brake/Run Relay Circuit
Short to Battery GEM REFER to
Section 501 - 16 .
B1434 Wiper Hi/Low Speed Relay Coil
Circuit Failure GEM REFER to
Section 501 - 16 .
B1436 Wiper Hi/Low Speed Relay Coil
Circuit Short to Battery GEM REFER to
Section 501 - 16 .
B1438 Wiper Mode Select Switch
Circuit Failure GEM REFER to
Section 501 - 16 .
B1441 Wiper Mode Select Switch
Circuit Short to Ground GEM REFER to
Section 501 - 16 . Klj . 8 ba
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