2003 FORD MUSTANG ECU

To exit the instrument cluster self-
diagnostic mode, turn the ignition switch to the OFF position or press
and hold the SELECT/RESET button for three or more seconds and release. z
93- 102 = 6.9- 9.1 volts (low voltage)
z 115- 124 = 8.5- 10.7 volts (norm band start)
z 215- 225 = 15.8- 18 volts (norm band end)
z 230- 241 = 16.9- 19.1 volts (high voltage) rhEo Displays the present decimal rheostat dimming input, 0-
255 (used when requesting
assistance from the hotline). rhi
rhS rho Not used.
Cr Displays the present RUN/START sense input. Display will show -
h for high input with
the ignition switch in the START position and - L for low input with the ignition switch in
the RUN position. PA-
PE7 Not used.
GAGE Repeats test display cycle.
Instrument Cluster Diagnostic Trouble Code (DTC) Index Diagnostic
Tool
Displayed DTC Self-
Diagnostic
Mode Displayed DTC Description Source Action
B1202 9202 Fuel Sender
Open Circuit Instrument
Cluster Go To Pinpoint Test B .
B1204 9204 Fuel Sender
Short to Ground Instrument
Cluster Go To Pinpoint Test B .
B1317 9317 Battery Voltage
High Instrument
Cluster Section 414 - 00 .
B1318 9318 Battery Voltage
Low Instrument
Cluster Section 414 - 00 .
B1342 9342 ECU is Defective Instrument
Cluster INSTALL a new instrument
cluster; REFER to Instrument Cluster in this section. TEST the
system for normal operation. B1343 9343 Heated Backlight
Input Circuit Failure Instrument
Cluster Section 501 - 11 .
B1356 9356 Ignition Run
Circuit Open Instrument
Cluster Go To Pinpoint Test A .
B1364 9364 Ignition Start
Circuit Open Instrument
Cluster Go To Pinpoint Test A .
B2143 A143 Odometer NVM
Mmory Failure Instrument
Cluster Go To Pinpoint Test J .
C1284 5284 Oil Pressure
Switch Failure Instrument
Cluster Go To Pinpoint Test C .
P1197 1197 Mileage Switch
Circuit Failure Instrument
Cluster Go To Pinpoint Test J . Klj . 7 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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PINPOINT TEST N: THE CHECK FUEL CAP INDICATOR IS NEVER
ON Test Step Result / Action to Take
M1 CHECK THE O/D OFF
INDICATOR OPERATION z
Key in ON position.
z Observe the O/D OFF indicator.
z Is the O/D OFF indicator
always on? Yes
GO to
M2 .
No
GO to M3 .
M2 CHECK THE INSTRUMENT
CLUSTER z
Key in OFF position.
z Disconnect: Instrument Cluster
C220a.
z Key in ON position.
z Observe the O/D OFF indicator.
z Did the indicator turn off? Yes
REFER to the Powertrain Control/Emissions Diagnosis
(PC/ED) manual.
No
GO to
M4 .
M3 CHECK THE INSTRUMENT
CLUSTER OPERATION z
Carry out the instrument cluster
self- diagnostic mode.
z Did the O/D OFF indicator
illuminate? Yes
REFER to the Powertrain Control/Emissions Diagnosis
(PC/ED) manual.
No
GO to
M4 .
M4 CHECK FOR CORRECT
INSTRUMENT CLUSTER
OPERATION z
Disconnect all instrument cluster
connectors.
z Check for:
zcorrosion
z pushed- out pins
z Connect all instrument cluster
connectors and make sure they
seat correctly.
z Operate the system and verify
the concern is still present.
z Is the concern still present? Yes
INSTALL a new instrument cluster. REFER to
Instrument Cluster
in this section. TEST the system for
normal operation.
No
The system is operating correctly at this time. Concern
may have been caused by a loose or corroded
connector. CLEAR the DTCs. REPEAT the self- test. Test Step Result / Action to Take
N1 RETREIVE AND RECORD DTCS FROM
CONTINUOUS AND ON- DEMAND SELF-TESTS—
PCM NOTE:
Once the check fuel cap indicator
does turn on, it does not turn off unless the
fuel cap has been correctly secured and the
vehicle has been driven for several minutes.
z Use recorded PCM DTCs from the
continuous and on- demand self-test.
z Are any DTCs recorded? Yes
If PCM DTC P0457, REFER to the
Powertrain Control/Emissions Diagnosis
(PC/ED) manual.
No
GO to
N2 .
N2 CARRY OUT THE INSTRUMENT CLUSTER Klj . 27 ba
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4. If the concern remains after the inspection, connect the diagnostic tool to the data link connector
(DLC) located beneath the instrument panel and select the vehicle to be tested from the
diagnostic tool menu. If the diagnostic tool does not communicate with the vehicle:
zcheck that the program card is correctly installed.
z check the connections to the vehicle.
z check the ignition switch position.
5. If the diagnostic tool still does not communicate with the vehicle, refer to the diagnostic tool manual.
6. Carry out the Data Link Diagnostic Test. If the diagnostic 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 NO RESP/NOT EQUIP for RCM, refer to Section 501 - 20B .
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.
7. If the DTCs retrieved are related to the concern, go to the GEM Diagnostic Trouble Code (DTC) Index to continue diagnostics.
8. If no DTCs related to the concern are retrieved, proceed to the Symptom Chart to continue diagnostics.
9. If the DTCs retrieved are for the RCM, refer to Section 501 - 20B .
Visual Inspection Chart Mechanical Electrical
z
Switch(es) z
Central junction box (CJB) fuses:
„28 (15A)
„ 32 (15A)
„ 39 (5A)
z Circuitry
GEM Diagnostic Trouble Code (DTC) Index DTC Description Source Action
B1340 Chime Input Request
Circuit Short to Ground GEM Go To Pinpoint Test C .
B1342 ECU Is Defective GEM CLEAR the DTCs. TEST the system for normal operation.
RETRIEVE the DTCs. If DTC B1342 is retrieved, INSTALL
a new GEM. REFER to
Section 419 - 10 .
B1353 Ignition Key-
In Circuit
Open GEM Go To Pinpoint Test B .
B1462 Safety Belt Switch
Circuit Failure GEM Go To Pinpoint Test F . Klj . 3 ba
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PINPOINT TEST B: POOR RECEPTION z
Are the resistances less than 5 ohms? system for normal
operation.
No
REPAIR the circuit
(s) in question. TEST
the system for
normal operation.
Test Step Result / Action to Take
B1 CHECK ANTENNA CABLE
CONNECTIONS z
Key in OFF position.
z Check the antenna connections
including the extension cable.
z Check to make sure the antenna is
securely mounted to the vehicle body
at ground points.
z Are the connections clean, secure,
and in metal- to-metal contact? Yes
GO to
B2 .
No
CLEAN and SECURE the antenna connections
as necessary. TEST the system for normal
operation. B2 CHECK SUPPRESSION
EQUIPMENT/MOUNTING AND
CONNECTING CIRCUITS z
Check all necessary suppression
equipment and the radio frequency
interference suppression bond. Refer
to Section 415 - 01 .
z Check the radio receiver hood bonding
strap and the body- to-chassis straps
for integrity, cleanliness, and metal- to-
metal contact.
z NOTE: The capacitor mounting points
are used to complete the electrical
circuit and must be mounted securely
to clean surfaces.
z Check the mounting and connecting
circuits of the radio ignition interference
capacitor for integrity, cleanliness, and
metal- to-metal contact.
z Are the connections clean, secure,
and in metal- to-metal contact? Yes
GO to
B3 .
No
CLEAN, SECURE, or INSTALL new suppression
equipment as necessary. TEST the system for
normal operation. B3 CHECK RADIO IGNITION
INTERFERENCE CAPACITOR z
Check the operation of the radio
ignition interference capacitor by
substituting it with a known good
component.
z Key in START position.
z Turn the audio unit on and check the
radio reception. Yes
INSTALL a new radio ignition interference
capacitor. TEST the system for normal operation.
No
GO to
B4 . Klj . 5 ba
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4. If the concern remains after the inspection, connect the scan tool to the data link connector
(DLC) located beneath the instrument panel and select the vehicle to be tested from the scan
tool menu. If the scan tool does not communicate with the vehicle:
zcheck that the program card is correctly installed.
z check the connections to the vehicle.
z check the ignition switch position.
5. If the scan tool still does not communicate with the vehicle, refer to the scan tool manual.
6. 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.
7. If the DTCs retrieved are related to the concern, go to GEM Diagnostic Trouble Code (DTC) Index to continue diagnostics.
8. If no DTCs related to the concern are retrieved, proceed to Symptom Chart to continue diagnostics.
GEM Diagnostic Trouble Code (DTC) Index Visual Inspection Chart Mechanical Electrical
z
Switch(es) z
CJB Fuses:
„7 (20A)
„ 32 (15A)
„ 39 (5A)
z Wiring harness
z Connections
z Lamps
z Circuitry
GEM Diagnostic Trouble Code (DTC) Index DTC Description Source Action
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 .
B1342 ECU Is Defective GEM CLEAR the DTC. Retrieve the DTCs. If DTC B1342 is
retrieved, INSTALL a new GEM. For additional information, REFER to Section 419 - 10 .
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 . Klj . 3 ba
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PINPOINT TEST PC: DATA LINK DIAGNOSTICS NETWORK TEST
Symptom Chart
Test Step Result / Action to Take
PC1 DATA LINK
DIAGNOSTICS NETWORK
TEST z
Run the Data Link
Diagnostics Network
Test.
z Is SYSTEM PASSED
obtained? Yes
Test PASSED. RETURN to the Symptom Chart of the section
for the module in question.
No
If no response from the diagnostic tool, GO to
Pinpoint Test H .
If CKT70=ALL ECUS NO RESP / NOT EQUIP, GO to Pinpoint Test F .
If CKT914 or CKT915=ALL ECUS NO RESP / NOT EQUIP,
GO to Pinpoint Test G .
If CKT70, CKT914, or CKT915=SOME ECUS NO RESP/NOT
EQUIP, REFER to Symptom Chart.
If the module in question is NO RESPONSE ON CKT914
(BUS+), or NO RESPONSE ON CKT915 (BUS-), REFER to
Symptom Chart.
If the module in question is NO RESPONSE/NOT EQUIPPED,
REFER to Symptom Chart.
Symptom Chart Condition
Possible Sources Action
z The module does not
respond to the diagnostic
tool — anti-lock brake control
module z
Wire or connection in SCP
communication network
(with traction control).
z Wire or connection in ISO
9141 communication
network (without traction
control).
z Anti- lock brake control
module without traction
control (optional).
z Anti- lock brake control
module with traction
control (optional). z
GO to
Pinpoint Test A .
z The module does not
respond to the diagnostic
tool — generic electronic
module (GEM) z
Wire or connection in ISO
9141 communication
network.
z GEM. z
GO to
Pinpoint Test B .
z The module does not
respond to the diagnostic
tool — restraint control
module (RCM) z
Wire or connection in ISO
9141 communication
network.
z RCM. z
GO to
Pinpoint Test C .
z The module does not
respond to the diagnostic z
Wire or connection in SCP
communication network. z
GO to
Pinpoint Klj . 3 ba
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DESCRIPTION AND OPERATION
Anti-
Theft — Passive Anti- Theft System (PATS)
The passive anti- theft system (PATS) contains the following components:
z theft indicator
z encoded ignition key
z transceiver module
z instrument cluster
z powertrain control module (PCM)
z standard corporate protocol (SCP) communication network
The PATS uses radio frequency identification technology to deter a driveaway theft. Passive means
that it does not require any activity from the user. This system is known as SecuriLock® in North
America, Safeguard® in the U.K. and PATS in continental Europe. This information can be found in
owners literature.
The PATS uses a specially encoded ignition key. Each encoded ignition key contains a permanently
installed electronic device called a transponder. Each transponder contains a unique electronic
identification code, with over 72 million billion combinations.
Each encoded ignition key must be programmed into the vehicle's instrument cluster (the instrument
cluster is also known as a hybrid electronic cluster [HEC]), before it can be used to start the engine.
There are special diagnostic procedures outlined in the workshop manual that must be carried out if
new encoded ignition keys are to be installed.
The encoded key is larger than a traditional ignition key. The key does not require batteries and should
last the life of the vehicle.
The transceiver module communicates with the encoded ignition key. This module is located behind
the steering column shroud and contains an antenna connected to a small electronics module. During
each vehicle start sequence, the transceiver module reads the encoded ignition key identification code
and sends the data to the instrument cluster.
The control functions are contained in the instrument cluster. This module carries out all of the PATS
functions such as receiving the identification code from the encoded ignition key and controlling engine
enable. The instrument cluster initiates the key interrogation sequence when the vehicle ignition switch
is turned to RUN or START.
The PATS uses the PCM to enable or disable the engine. The instrument cluster communicates with
the PCM over the SCP network in order to enable engine operation. The instrument cluster and the
PCM use sophisticated messages in order to prevent a theft. The instrument cluster and the PCM
share security data (when first installed together) that makes them a matched pair. After this security
data sharing, these modules will not function in other vehicles. The shared PCM ID is remembered
even if the battery is disconnected. The instrument cluster also stores the vehicle's key identification
code even if the battery is disconnected. There are special diagnostic procedures outlined in this
workshop manual that may be carried out if either a new instrument cluster or PCM needs to be
installed.
All elements of PATS must be functional before the engine is allowed to start. If any of the components
are not working correctly, the vehicle will not start.
PATS uses a visual theft indicator. This indicator will prove out for three seconds when the ignition SECTION 419-
01: Anti-Theft — PATS 2003 Mustang Workshop Manual Klj . 1 ba
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