key FORD MUSTANG 2003 Workshop Manual

z
Disconnect: Clockspring C218b.
z Measure the resistance between clockspring C218b, circuit 614
(GY/OG) and circuit 615 (GY/WH), harness side.
z Is the resistance greater than 10,000 ohms? Yes
INSTALL a new
clockspring. GO to
J6
.
No
REPAIR the circuit
(s) as necessary.
GO to J6 .
J5 CHECK FOR AN INTERMITTENT FAULT
z
Refer to the continuous DTCs recorded during Step J1.
z Was the continuous DTC retrieved during Step J1 an
intermittent fault? Yes
CHECK for causes
of intermittent low
resistance 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
J6 .
No
GO to J6 .
J6 CHECK FOR ADDITIONAL DTCs
z
Refer to the continuous DTCs recorded during Step J1.
z Were any continuous DTCs retrieved during Step J1? 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 Klj . 28 ba
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Pinpoint Test K: LFC 35/DTC B1935 —
Passenger Air Bag Circuit Resistance Low
Normal Operation
The restraints control module (RCM) monitors the resistance of the passenger air bag ignitor by
measuring the resistance between pins 6 and 7. If the RCM detects low resistance between these
pins, it will store a diagnostic trouble code (DTC) B1935 in memory and flash a lamp fault code (LFC)
35 (or higher priority code if one exists) on the air bag indicator.
Possible Causes
Passenger air bag low resistance can be caused by:
za short in the wiring harness.
z a low resistance in the passenger air bag module.
z an RCM internal concern.
z a worn or damaged connector shorting bar or camming beam.
PINPOINT TEST K: LFC 35/DTC B1935 — PASSENGER AIR BAG
CIRCUIT RESISTANCE LOW (SRS) in this
section. CLEAR all
DTCs. Test Step Result / Action to
Take K1 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 B1935 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 K2 .
No
This is an
intermittent fault.
The fault condition
is not present at
this time. GO to
K4 .
K2 CHECK THE PASSENGER 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. Yes
GO to
K3 .
No
INSTALL a new Klj . 29 ba
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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
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 B1935 retrieved? passenger air bag
module. GO to
K5 .
K3 CHECK THE PASSENGER AIR BAG MODULE CIRCUIT
z
Key in OFF position.
z Disconnect: Passenger Air Bag Restraint System Diagnostic Tool.
z Measure the resistance between passenger air bag C256, circuit 607
(LB/OG), harness side and passenger air bag C256, circuit 616
(PK/BK), harness side.
z Is the resistance greater than 10,000 ohm? Yes
INSTALL a new
RCM. GO to
K5 .
No
REPAIR the circuit
(s) as necessary.
GO to K5 .
K4 CHECK FOR AN INTERMITTENT FAULT
z
Refer to the continuous DTCs recorded during Step K1.
z Was the continuous DTC retrieved during Step K1 an
intermittent fault? Yes
CHECK for causes
of intermittent low
resistance on
circuit 607 (LB/OG)
and circuit 616
(PK/BK). Attempt
to recreate the
hard fault by
flexing the wire
harness and
cycling the ignition
key frequently.
REPAIR any
intermittent Klj . 30 ba
462003 Mustang Workshop Manual
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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 B1892 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
L2 .
No
This is an
intermittent fault.
The fault condition
is not present at
this time. GO to
L5 .
L2 CHECK THE AIR BAG TONE WARNING INDICATOR CIRCUIT
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
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 Disconnect: RCM C2041.
z Disconnect: GEM C201e.
z Measure the resistance between RCM C2041 pin 26, circuit 1083
(LB/BK), harness side and RCM C2041 pin 21, circuit 397 (BK/WH),
harness side. Yes
REPAIR the
circuit. GO to
L6 .
No
GO to L3 . Klj . 32 ba
462003 Mustang Workshop Manual
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z
Is the resistance less than 10,000 ohms? L3 CHECK THE AIR BAG TONE WARNING INDICATOR MODULE
CIRCUIT z
Measure the resistance between RCM C2041 pin 26, circuit 1083
(LB/BK), harness side and GEM C201e pin 10, circuit 1083 (LB/BK),
harness side.
z Is the resistance greater than 10 ohms? Yes
REPAIR the
circuit. GO to
L6 .
No
GO to L4 .
L4 CHECK THE AIR BAG TONE WARNING INDICATOR
z
Disconnect: GEM C201e.
z Key in ON position.
z Measure the voltage between RCM C2041 pin 26, circuit 1083
(LB/BK), harness side and ground. Yes
INSTALL a new
GEM. GO to
L6 .
No
INSTALL a new
RCM. GO to L6 . Klj . 33 ba
462003 Mustang Workshop Manual
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Pinpoint Test M: DTC B1891 —
Air Bag Tone Warning Indicator Circuit Shorted to Battery or
Ignition
Normal Operation
The restraints control module (RCM) monitors its connection to the generic electronic module (GEM) at
pin 10. This connection is used to signal a chime if the air bag indicator is inoperative and another SRS
fault exists. If the RCM detects a short to battery or ignition on the connection to the GEM, it will store
a diagnostic trouble code (DTC) B1891 in memory.
Possible Causes z
Is the voltage less than 1.0 volt? L5 CHECK FOR AN INTERMITTENT FAULT
z
Refer to the continuous DTCs recorded during Step L1.
z Was the continuous DTC retrieved during Step L1 an
intermittent fault? Yes
CHECK for causes
of intermittent
short to ground or
open on circuit
1083 (LB/BK).
Attempt to recreate
the hard fault by
flexing the wire
harness and
cycling the ignition
key frequently.
REPAIR any
intermittent
concerns found.
GO to
L6 .
No
GO to L6 .
L6 CHECK FOR ADDITIONAL DTCs
z
Refer to the continuous DTCs recorded during Step L1.
z Were any continuous DTCs retrieved during Step L1? 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 . 34 ba
462003 Mustang Workshop Manual
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An air bag tone warning indicator circuit short to battery or ignition can be caused by:
za short to battery or ignition on circuit 1083 (LB/BK).
z a damaged or inoperative GEM.
z an RCM internal concern.
PINPOINT TEST M: DTC B1891 — AIR BAG TONE WARNING
INDICATOR CIRCUIT SHORTED TO BATTERY OR IGNITION Test Step Result / Action to
Take M1 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 B1891 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
M2 .
No
This is an
intermittent fault.
The fault condition
is not present at
this time. GO to
M4 .
M2 CHECK THE AIR BAG TONE WARNING INDICATOR CIRCUIT
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
over the road. NOTE: The SRS must be fully operational and free of
faults before releasing the vehicle to the customer. Yes
GO to
M3 .
No
REPAIR the
circuit. GO to M5 . Klj . 35 ba
462003 Mustang Workshop Manual
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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 Disconnect: RCM C2041.
z Disconnect: GEM C201e.
z Key in ON position.
z Measure the voltage between RCM C2041 pin 26, circuit 1083
(LB/BK), harness side and ground.
z Is the voltage less than 0.2 volt? M3 CHECK THE AIR BAG TONE WARNING INDICATOR
z
Key in OFF position.
z Connect: GEM C201e.
z Key in ON position.
z Jumper RCM C2041 pin 26, circuit 1083 (LB/BK), harness side to
ground.
z Does the GEM generate a tone? Yes
INSTALL a new
RCM. GO to
M5 .
No
INSTALL a new
GEM. GO to M5 .
M4 CHECK FOR AN INTERMITTENT FAULT
z
Refer to continuous DTCs recorded during Step M1.
z Was the continuous DTC retrieved during step M1 an
intermittent fault? Yes
Check for causes
of intermittent
short to ground or
open on circuit
1083 (LB/BK).
Attempt to recreate
the hard fault by
flexing the wire
harness and
cycling the ignition
key frequently.
REPAIR any
intermittent
concerns found.
GO to
M5 .
No
GO to M5 . Klj . 36 ba
462003 Mustang Workshop Manual
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Test Step Result / Action to
Take N1 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 B1869 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
N2 .
No
This is an
intermittent fault.
The fault
conditions not
present at this
time. GO to N5 .
N2 CHECK THE RCM
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
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 Disconnect: RCM C2041.
z Measure the resistance between RCM C2041 pin 20, component
side and a known good chassis ground. Yes
INSTALL a new
RCM. GO to
N6 .
No
GO to N3 . Klj . 38 ba
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z
Is the resistance less than 10 ohms? N3 CHECK CIRCUIT 608 (BK/YE) FOR A SHORT TO GROUND
z
Key in OFF position.
z Disconnect: Instrument Cluster C220a.
z Measure the resistance to ground at instrument cluster C220a pin 12,
circuit 608 (BK/YE).
z Is the resistance less than 100 ohms? Yes
REPAIR the
circuit. GO to
N6 .
No
GO to N4 .
N4 CHECK CIRCUIT 608 (BK/YE) FOR AN OPEN
z
Disconnect: Instrument Cluster C220a.
z Measure the resistance between RCM C2041 pin 20, circuit 608
(BK/YE), harness side and instrument cluster C220a pin 12, circuit
608 (BK/YE), harness side. Yes
REPAIR the
circuit. GO to
N6 .
No
REPAIR the
instrument cluster.
GO to N6 . Klj . 39 ba
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