pinpoint test b FORD MUSTANG 2003 Repair Manual

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 .
B1410 Driver Power Window Motor
Circuit Failure GEM REFER to
Section 501 - 11 .
B1426 Lamp Safety Belt Circuit Short
to Battery GEM REFER to
Section 413 - 01 .
B1428 Lamp Safety Belt Circuit Failure GEM REFER to
Section 413 - 01 .
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 .
B1446 Wiper Park Sense Circuit
Failure GEM REFER to
Section 501 - 16 .
B1448 Wiper Park Sense Circuit Short
to Battery GEM REFER to
Section 501 - 16 .
B1450 Wiper Wash/Delay Switch
Circuit Failure GEM REFER to
Section 501 - 16 .
B1453 Wiper Wash/Delay Switch
Circuit Short to Ground GEM REFER to
Section 501 - 16 .
B1458 Wiper Washer Pump Motor
Relay Circuit Failure GEM REFER to
Section 501 - 16 .
B1460 Wiper Washer Pump Motor
Relay Coil Circuit Short to Battery GEM REFER to
Section 501 - 16 .
B1462 Safety Belt Switch Circuit
Failure GEM REFER to
Section 413 - 09 .
B1466 Wiper Hi/Low Speed Not
Switching GEM REFER to
Section 501 - 16 .
B1473 Wiper Low Speed Circuit Motor
Failure GEM REFER to
Section 501 - 16 .
B1476 Wiper High Speed Circuit Motor
Failure GEM REFER to
Section 501 - 16 .
B1551 Decklid Release Circuit Failure GEM REFER to
Section 501 - 14B .
B1553 Decklid Release Circuit Short
to Battery GEM REFER to
Section 501 - 14B .
B1555 Ignition Run/Start Circuit
Failure GEM GO to
Pinpoint Test D .
B1687 Lamp Dome Input Circuit Short
to Battery GEM REFER to
Section 417 - 02 .
B2486 LF Side Repeater Lamp Output GEM REFER to
Section 417 - 01 . Klj . 3 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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PINPOINT TEST B: THE IGNITION SWITCH IS INOPERATIVE 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 2 400 (LB/BK)
C201a 3 1006 (DG/WH)
C201b 1 1001 (WH/YE)
C201b 4 193 (YE/LG) 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 2,
circuit 397 (BK/WH), harness side and ground.
z Is the resistance less than 5 ohms? Yes
GO to
A3 .
No
REPAIR the circuit(s) in
question. TEST the system
for normal operation. A3 CHECK CIRCUIT 397 (BK/WH) FOR SHORT TO POWER
z
Measure the voltage between GEM C201b pin 2, circuit 397
(BK/WH), harness side and ground.
z Is any voltage present? Yes
REPAIR the circuit. TEST
the system for normal
operation.
No
REFER to
Section 418 - 00 .
Test Step Result / Action to Take
B1 CHECK THE IGNITION SWITCH
z
Carry out the ignition switch component test.
REFER to Wiring Diagrams Cell 149,
Component Testing.
z Is the ignition switch OK ? Yes
INSTALL a new BJB. TEST the system for
normal operation. Klj . 5 ba
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PINPOINT TEST C: NO POWER IN ACC
PINPOINT TEST D: NO POWER IN RUN
PINPOINT TEST E: NO POWER IN START No
INSTALL a new ignition switch. REFER to
Ignition Switch
. TEST the system for
normal operation. Test Step Result / Action to Take
C1 CHECK THE RADIO FOR NORMAL OPERATION
z
Key in ON position.
z Check the radio for normal operation.
z Does the radio operate correctly? Yes
GO to
C2 .
No
Go To Pinpoint Test D .
C2 CHECK THE VOLTAGE AT THE IGNITION SWITCH
z
Disconnect: Ignition Switch C250 .
z Measure the voltage between ignition switch C250 Pin B5,
Circuit 1050 (LG/VT), harness side and ground.
z Is the voltage greater than 10 volts? Yes
INSTALL a new ignition
switch. REFER to
Ignition Switch . TEST the system for
normal operation.
No
REPAIR the circuit. TEST the
system for normal operation. Test Step Result / Action to Take
D1 CHECK THE IGNITION SWITCH
z
Carry out the ignition switch component test.
REFER to Wiring Diagrams Cell 149,
Component Testing.
z Is the ignition switch OK ? Yes
INSTALL a new BJB. TEST the system for
normal operation.
No
INSTALL a new ignition switch. REFER to
Ignition Switch
. TEST the system for
normal operation. Test Step Result / Action to Take
E1 CHECK THE VOLTAGE TO THE IGNITION SWITCH
z
Key in OFF position.
z Disconnect: Ignition Switch C250 . Yes
GO to
E2 . Klj . 6 ba
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1. If compression improves considerably, piston rings are faulty.
2. If compression does not improve, valves are sticking or seating incorrectly.
3. If two adjacent cylinders indicate low compression pressures and squirting oil on each piston
does not increase compression, the head gasket may be leaking between cylinders. Engine oil
or coolant in cylinders could result from this condition.
Use the Compression Pressure Limit Chart when checking cylinder compression so that the
lowest reading is within 75 percent of the highest reading.
Cylinder Leakage Detection
When a cylinder produces a low reading, use of the Engine Cylinder Leak Detection/Air Pressurization
Kit will be helpful in pinpointing the exact cause.
The leakage detector is inserted in the spark plug hole, the piston is brought up to dead center on the
compression stroke, and compressed air is admitted.
Once the combustion chamber is pressurized, a special gauge included in the kit will read the
percentage of leakage. Leakage exceeding 20 percent is excessive.
While the air pressure is retained in the cylinder, listen for the hiss of escaping air. A leak at the intake
valve (6507) will be heard in the throttle body (9E926). A leak at the exhaust valve (6505) can be
heard at the tail pipe. Leakage past the piston rings will be audible at the positive crankcase ventilation
(PCV) connection. If air is passing through a blown head gasket to an adjacent cylinder, the noise will
be evident at the spark plug hole of the cylinder into which the air is leaking. Cracks in the cylinder
block or gasket leakage into the cooling system may be detected by a stream of bubbles in the radiator
(8005).
Oil Consumption Test
The following diagnostic procedure is used to determine the source of excessive internal oil
consumption. 1. NOTE: Oil use is normally greater during the first 16,100 km (10,000 miles) of service. As
mileage increases, oil use generally decreases. Vehicles in normal service should get at least
1,450 km per liter (900 miles per quart) after 16,000 km (10,000 miles) of service. High speed
driving, towing, high ambient temperature and other factors may result in greater oil use.
Define excessive oil consumption, such as the number of miles driven per liter (quart) of oil
used. Also determine customer's driving habits, such as sustained high speed operation,
towing, extended idle and other considerations.
2. Verify that the engine has no external oil leak as described under Engine Oil Leaks in the Diagnosis and Testing portion of this section.
3. Verify that the engine has the correct oil level dipstick (6750).
4. Verify that the engine is not being run in an overfilled condition. Check the oil level at least five minutes after a hot shutdown with the vehicle parked on a level surface. In no case should the
level be above MAX or the letter F in FULL. If significantly overfilled, carry out Steps 6a through
6d.
5. Verify the spark plugs are not oil saturated. If the spark plugs are oil saturated and compression is good it can be assumed the valve seals or valve guides are at fault. Klj . 9 ba
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Intake Manifold Vacuum Test
Bring the engine to normal operating temperature. Connect the Vacuum/Pressure Tester to the intake
manifold. Run the engine at the specified idle speed.
The vacuum gauge should read between 51-
74 kPa (15-22 in-Hg) depending upon the engine
condition and the altitude at which the test is performed. Subtract 4.0193 kPa (1 in- Hg) from the
specified reading for every 304.8 m (1,000 feet) of elevation above sea level.
The reading should be steady. If necessary, adjust the gauge damper control (where used) if the
needle is fluttering rapidly. Adjust the damper until the needle moves easily without excessive flutter.
Intake Manifold Vacuum Test—Interpreting Vacuum Gauge Readings
A careful study of the vacuum gauge reading while the engine is idling will help pinpoint trouble areas.
Always conduct other appropriate tests before arriving at a final diagnostic decision. Vacuum gauge
readings, although helpful, must be interpreted carefully.
Most vacuum gauges have a normal band indicated on the gauge face.
The following are potential gauge readings. Some are normal; others should be investigated further.
1. NORMAL READING: Needle between 51- 74 kPa (15-22 in-Hg) and holding steady.
2. NORMAL READING DURING RAPID ACCELERATION AND DECELERATION: When the engine is rapidly accelerated (dotted needle), the needle will drop to a low reading (not to zero).
When the throttle is suddenly released, the needle will snap back up to a higher than normal
figure.
3. NORMAL FOR HIGH- LIFT CAMSHAFT WITH LARGE OVERLAP: The needle will register as low as 51 kPa (15 in - Hg) but will be relatively steady. Some oscillation is normal. Klj . 11 ba
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„
If coolant is low, add specified coolant mixture only.
„ If the engine coolant tests too weak, add straight engine coolant until the readings
are within acceptable levels.
„ If the engine coolant tests strong, remove some of the engine coolant and add
water until the readings are within acceptable levels.
5. If the concern remains after the inspection, determine the symptom(s) and GO to Symptom Chart
Symptom Chart
Pinpoint Tests
PINPOINT TEST A: LOSS OF COOLANT
Symptom Chart Condition
Possible Sources Action
z Loss of coolant zRadiator.
z Coolant pump seal.
z Radiator hoses.
z Heater hoses.
z Heater core.
z Engine gaskets.
z Degas bottle or
coolant expansion
tank. z
Go To Pinpoint Test
A .
z The engine overheats zThermostat.
z Coolant pump.
z Internal engine coolant
leak.
z Radiator.
z Cooling fan.
z Pressure relief cap or
radiator cap. z
Go To Pinpoint Test
B .
z The engine does not reach
normal operating temperature z
Thermostat. zGo To Pinpoint Test
C .
Test Step Result / Action to Take
A1 CHECK THE ENGINE COOLANT LEVEL
WARNING: Never remove the pressure relief cap
while the engine is operating or when the cooling system is
hot. Failure to follow these instructions can result in
damage to the cooling system or engine or personal injury.
To avoid having scalding hot coolant or steam blow out of
the degas bottle when removing the pressure relief cap,
wait until the engine is cooled, then wrap a thick cloth
around the pressure relief cap and turn it slowly. Step back Yes
GO to
A2 .
No
REFILL the engine
coolant as necessary.
GO to A2 . Klj . 3 ba
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PINPOINT TEST B: THE ENGINE OVERHEATS
Test Step Result / Action to
Take B1 CHECK THE ENGINE COOLANT LEVEL
WARNING: Never remove the pressure relief cap while
the engine is operating or when the cooling system is hot.
Failure to follow these instructions can result in damage to
the cooling system or engine or personal injury. To avoid
having scalding hot coolant or steam blow out of the degas
bottle when removing the pressure relief cap, wait until the
engine is cooled, then wrap a thick cloth around the
pressure relief cap and turn it slowly. Step back while the
pressure is released from the cooling system. When you are
sure all the pressure has been released, turn and remove
the pressure relief cap (still with a cloth). NOTE: If the engine
is hot, allow the engine to cool before proceeding.
z Key in OFF position.
z Check the engine coolant level at the degas bottle/coolant
expansion tank.
z Is the engine coolant OK? Yes
GO to
B2 .
No
REFILL the engine
coolant at the degas
bottle/coolant
expansion tank. Go To Pinpoint Test A .
B2 CHECK THE COOLANT CONDITION
z
Check the coolant for dirt, rust or contamination.
z Is the coolant condition OK? Yes
GO to
B3 .
No
FLUSH the engine
cooling system.
REFER to Engine and Radiator Flushing in
this section. TEST the
system for normal
operation. B3 CHECK FOR AN AIRFLOW OBSTRUCTION
z
Inspect the A/C condenser core and radiator for obstructions
such as leaves or dirt.
z Is there an obstruction? Yes
REMOVE the
obstruction. CLEAN the
A/C condenser core
and radiator. TEST the
system for normal
operation.
No
GO to
B4 .
B4 CHECK THE WATER THERMOSTAT OPERATION
z
Start the engine and allow the engine to run for ten minutes.
z Feel the inlet and outlet heater water hoses and the underside of
the upper radiator hose.
z Are the upper radiator hose and the heater water hoses
cold? Yes
INSTALL a new water
thermostat. REFER to
Thermostat
— 3.8L ,
Thermostat — 4.6L(2V)
or
Thermostat — 4.6L
(4V) in this section.
TEST the system for
normal operation.
No
GO to B5 . Klj . 5 ba
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PINPOINT TEST C: THE ENGINE DOES NOT REACH NORMAL
OPERATING TEMPERATURE
Component Tests
Pressure Test —
3.8L
WARNING: Never remove the pressure relief cap while the engine is operating or when the
cooling system is hot. Failure to follow these instructions can result in damage to the cooling
system or engine or personal injury. To avoid having scalding hot coolant or steam blow out of
the degas bottle when removing the pressure relief cap, wait until the engine is cooled, then
wrap a thick cloth around the pressure relief cap and turn it slowly. Step back while the
pressure is released from the cooling system. When you are sure all the pressure has been
released, turn and remove the pressure relief cap (still with a cloth).
1. Remove the radiator cap. Fill the radiator as needed. Fit the pressure tester to the radiator neck, using an aftermarket adapter.
2. CAUTION: Do not pressurize the cooling system beyond 110 kPa (16 psi).
Pump the cooling system to a maximum of 102 kPa (14.9 psi) and hold for 2 minutes. If the
pressure drops within this time, inspect for leaks and repair as necessary. Pressure Test — 4.6L B5 CHECK THE COOLING FAN OPERATION
z
Carry out the cooling fan component tests. Go to Component
Tests.
z Is the cooling fan operation OK? Yes
For diagnosis and
testing of the engine,
REFER to
Section 303 -
00 .
No
INSTALL a new fan
component as
necessary. TEST the
system for normal
operation. Test Step Result / Action to Take
C1 CHECK THE ENGINE
TEMPERATURE z
Start the engine and allow the
engine to idle for ten minutes.
z Feel the inlet and heater water
hoses and the underside of the
upper radiator hose.
z Are the upper radiator hose
and the heater water hoses
cold? Yes
INSTALL a new water thermostat. REFER to
Thermostat
— 3.8L ,
Thermostat — 4.6L(2V) or
Thermostat — 4.6L(4V) in this section. TEST the system
for normal operation.
No
For diagnosis and testing of the engine coolant
temperature gauge, REFER to Section 413 - 01 . Klj . 6 ba
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indicates higher water content than required.
„ NOTE: The addition of Motorcraft Cooling System Stop Leak Pellets, VC- 6,
darkens Motorcraft Premium Gold Engine Coolant from yellow to golden tan.
If Motorcraft Premium Gold Engine Coolant (yellow color) VC-7- A or equivalent
meeting Ford specification WSS- M97B51-A1 has a clear or pale yellow color, this
indicates higher water content than required.
„ Dark brown can indicate unauthorized stop leak may have been used. Use
Motorcraft Cooling System Stop Leak Pellets VC- 6 or equivalent meeting Ford
specification ESE-M99B37- 5 except as noted in ES-F65E-19A511- AA only.
„ A light or reddish brown color indicates that rust may be present in the cooling
system. Flush the system and refill with the correct mixture of water and engine
coolant.
„ An iridescent sheen on top of the coolant or a milky brown color can indicate a
trace of oil is entering the system. For additional information on engine diagnosis,
refer to Section 303 - 00 .
3. If the engine coolant appearance is acceptable, test the engine coolant freezing point
range with the special tool. The freezing point should be in the range - 50°F to -10°F. If
the vehicle is driven in cold climates less than - 34°F, it may be necessary to increase the
coolant concentration to get adequate freeze protection.
„Maximum coolant concentration is 60/40.
„ Minimum coolant concentration is 40/60.
4. Check the coolant system conditions:
„If the intercooler fluid is low, add the specified coolant mixture only.
„ If the intercooler coolant fluid tests weak, add straight engine coolant until the
readings are within acceptable levels.
„ If the engine coolant tests strong, remove some of the engine coolant and add
water until readings are within acceptable levels.
5. If the concern remains after the inspection, determine the symptom(s). GO to Symptom Chart .
6. Verify the cooling system is correctly filled and bled. Refer to Supercharger Cooling System Draining, Filling and Bleeding in this section.
Symptom Chart
Pinpoint Tests PINPOINT TEST A: LOSS OF COOLANT SYMPTOM CHART
Condition
Possible Sources Action
z Loss of intercooler
coolant z
Intercooler.
z Intercooler
radiator.
z Water pump.
z Coolant hoses.
z Degas bottle. z
Go To Pinpoint Test A . Klj . 3 ba
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