
Symptom:
P-1494 LEAK DETECTION PUMP PRESSURE SWITCH
When Monitored and Set Condition:
P-1494 LEAK DETECTION PUMP PRESSURE SWITCH
When Monitored: Immediately after a cold start, with ambient temperature between 4
deg C (40 deg F) and 32 deg C (90 deg F) and coolant temperature within ±12 deg C (10 deg
F) of ambient temperature.
Set Condition: The state of the switch does not change when the solenoid is energized.
POSSIBLE CAUSES
FUSED IGNITION SWITCH OUTPUT CIRCUIT OPEN
LDP PRESSURE SWITCH CIRCUIT SHORTED TO GROUND
LDP SWITCH SENSE CIRCUIT OPEN
LDP DEFECTIVE
LDP WIRING HARNESS INTERMITTENT DEFECT
LDP WIRING HARNESS OBSERVABLE DEFECT
LDP VACUUM HOSE LEAKING OR OBSTRUCTED
PCM DEFECTIVE
TEST ACTION APPLICABILITY
1 Start the engine and allow the engine to idle.
With the DRB, perform the Leak Detect Pump Test.
Select 1 to Pump.
Press the down arrow on the DRB several times.
The LEAK DETECT PUMP SW state should change from Open (UP) to CLOSED
(DN).
Did the Leak Detect Pump Switch state change as described?All
Ye s®Go To 2
No®Go To 4
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TEST ACTION APPLICABILITY
2 Ignition on, engine not running
With the DRB, read DTCs and Freeze Frame Data and record.
With the DRB, Clear DTCs.
Start the engine and allow the engine to idle.
With the DRB, perform the LDP Monitor test.
Wiggle the wiring harness and connectors from the LDP connector to the PCM
connector while the monitor is running.
Note: Be careful of the engine's moving parts.
With the DRB, Read DTCs.
Does the P-1494 Leak Detection Pump Sw or Mechanical Fault DTC return during
the wiggle test?All
Ye s®Repair the wiring harness or connector as necessary.
Perform Powertrain Verification Test VER-5A.
No®Go To 3
3 Ignition Off
Using the schematic as a guide, inspect the Wiring and Connectors.
Were any problems found?All
Ye s®Repair as necessary.
Perform Powertrain Verification Test VER-5A.
No®Test Complete.
4 Ignition Off
Disconnect the LDP Connector.
Note: Check connectors - Clean/repair as necessary.
Engine off, key on.
Using a voltmeter, probe the Fused Ignition Switch Output Circuit.
Is the voltage above 10.0 volts?All
Ye s®Go To 5
No®Repair the open Fused Ignition Switch Output Circuit.
Perform Powertrain Verification Test VER-5A.
5 Ignition Off
Disconnect the Engine Vacuum Supply Hose at the LDP.
Install a Vacuum Gauge to Engine Vacuum Supply Hose at the LDP.
Start engine and read Vacuum Gauge.
Does Vacuum Gauge read within 1 inch of engine vacuum?All
Ye s®Go To 6
No®Repair leak or obstruction in Vacuum Hose.
Perform Powertrain Verification Test VER-5A.
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DRIVEABILITY
P-1494 LEAK DETECTION PUMP PRESSURE SWITCH ÐContinued
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Symptom:
P-1495 LEAK DETECTION PUMP SOLENOID CIRCUIT
When Monitored and Set Condition:
P-1495 LEAK DETECTION PUMP SOLENOID CIRCUIT
When Monitored: Immediately after a cold start, with ambient temperature between 4
deg C (40 deg F) and 32 deg C (90 deg F) and coolant temperature within ±12 deg C (10 deg
F) of ambient temperature.
Set Condition: The state of the solenoid does not change.
POSSIBLE CAUSES
FUSED IGNITION SWITCH OUTPUT CIRCUIT OPEN
LDP DEFECTIVE
LDP SOLENOID CKT WIRING HARNESS INTERMITTENT DEF
LDP SOLENOID CKT WIRING HARNESS OBSERVABLE DEFECT
LDP SOLENOID CONTROL CIRCUIT OPEN
LDP SOLENOID CONTROL CIRCUIT SHORT TO GROUND
PCM DEFECTIVE
NO POSSIBLE CAUSES REMAINING
TEST ACTION APPLICABILITY
1 Ignition On, Engine Not Running
With the DRB, actuate the LDP Pump Solenoid.
Is it clicking?All
Ye s®Go To 2
No®Go To 5
2 Ignition On, Engine Not Running.
With the DRB, actuate the LDP Solenoid.
While monitoring the LDP Switch state, wiggle Wiring Harness from the LDP
Solenoid to PCM.
Did the LDP Switch state ever change from up to down when wiggled?All
Ye s®Repair as necessary where wiggling caused problem to appear.
Perform Powertrain Verification Test VER-6A.
No®Go To 3
3 Ignition Off
Using the schematic as a guide, inspect the Wiring and Connectors.
Were any problems found?All
Ye s®Repair as necessary.
Perform Powertrain Verification Test VER-6A.
No®Go To 4
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TEST ACTION APPLICABILITY
4 Check the freeze frame data to determine the conditions when code was set.
Attempt duplication of 'freeze frame' conditions for added diagnostics.
If there are no other possible causes remaining there is assumed to be an9intermit-
tent9problem with a Wiring Harness Connector or Wire.
View repair options.All
Repair
Visually inspect related Wire Harness Connectors and Harnesses.
Look for broken, bent, pushed out, or corroded terminals and for
chafed, pierced, or partiallly broken wire, respectively. Refer to
any hotlines or technical service bulletins that apply.
5 Ignition Off
Disconnect the LDP Solenoid.
Note: Check connectors - Clean/repair as necessary.
Key on.
Using a Voltmeter, measure the voltage of the Fused Ignition Switch Output Circuit
at the Solenoid Connector.
Is the voltage above 10.0 volts?All
Ye s®Go To 6
No®Repair the open Fused Ignition Switch Output Circuit.
Perform Powertrain Verification Test VER-6A.
6 Ignition Off
Disconnect the LDP Solenoid.
Note: Check connectors - Clean/repair as necessary.
Disconnect the PCM.
Note: Check connectors - Clean/repair as necessary.
Using an Ohmmeter, measure the resistance of the LDP Solenoid Control Circuit at
the PCM Connector to ground.
Is the resistance below 5.0 ohms?All
Ye s®Repair the LDP Solenoid Circuit for a short to ground.
Perform Powertrain Verification Test VER-6A.
No®Go To 7
7 Ignition Off
Disconnect the LDP Solenoid.
Note: Check connectors - Clean/repair as necessary.
Disconnect the PCM.
Note: Check connectors - Clean/repair as necessary.
With an Ohmmeter, measure the resistance of the LDP Solenoid Control Circuit from
the PCM Connector to the LDP Connector.
Is the resistance below 5.0 ohms?All
Ye s®Go To 8
No®Repair the open LDP Solenoid Control Circuit.
Perform Powertrain Verification Test VER-6A.
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DRIVEABILITY
P-1495 LEAK DETECTION PUMP SOLENOID CIRCUIT ÐContinued
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Symptom List:
P-1696 PCM FAILURE EEPROM WRITE DENIED
P-1697 PCM FAILURE SRI MILE NOT STORED
Test Note: All symptoms listed above are diagnosed using the same tests.
The title for the tests will be P-1696 PCM FAILURE EEPROM
WRITE DENIED.
POSSIBLE CAUSES
POWERTRAIN CONTROL MODULE DEFECTIVE9WRITE REFUSED9
SRI MEMORY / INSTRUMENT PANEL ODO MILEAGE SAME
SRI MEMORY9SRI MILEAGE INVALID9
SRI MEMORY NEEDS UPDATING
PCM DEFECTIVE9WRITE FAILURE9
TEST ACTION APPLICABILITY
1 Ignition on, engine not running.
With the DRB, perform the SRI Memory Test.
Does the DRB display9Write Refused9?All
Ye s®Go To 2
No®Go To 4
2 Ignition on, engine not running.
With the DRB, perform the SRI Memory Test.
Does the DRB display9Write Failure?9All
Ye s®Replace the Powertrain Control Module.
Perform Verification Test VER-2A.
No®Go To 3
3 Ignition on, engine not running.
With the DRB, perform the SRI Memory Test.
Note: Retest the SRI Memory two more times when necessary.
Did the trouble code9Write Refused9return?All
Ye s®Replace the Powertrain Control Module.
Perform Powertrain Verification Test VER-2A.
No®Test Complete.
4 Ignition on, engine not running.
With the DRB, perform the SRI Memory Test.
Does the DRB display9SRI Mileage Invalid?9All
Ye s®Update the mileage and retest the SRI Memory.
Perform Powertrain Verification Test VER-2A.
No®Go To 5
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Symptom:
* CHECKING PCM POWER AND GROUND CIRCUITS
POSSIBLE CAUSES
OPEN PCM GROUND CIRCUIT AT CAVITY 10
FUSED IGNITION SWITCH OUTPUT CIRCUIT OPEN
OPEN PCM GROUND CIRCUIT AT CAVITY 50
TEST ACTION APPLICABILITY
1 Ignition Off
Disconnect the PCM Connector.
Note: Check connectors - Clean/repair as necessary.
With an Ohmmeter, measure the ground circuits at cavities 10 and 50.
Is the resistance below 5.0 ohms?All
Ye s®Go To 2
No®Repair the open ground circuit(s).
Perform Verification Test VER-2A.
2 Ignition Off
Disconnect the PCM Connector.
Note: Check connectors - Clean/repair as necessary.
Turn Ignition on.
With a Voltmeter, measure the Fused Ignition Switch Output Circuit cavity 20.
Is the voltage above 10.0 volts?All
Ye s®Go To 3
No®Repair the open Fused Ignition Switch Output Circuit.
Perform Verification Test VER-2A.
3 Ignition Off
Disconnect the Powertrain Control Module Connector.
Note: Check connectors - Clean/repair as necessary.
Turn Ignition on.
Using a voltmeter, probe the fused B (+) circuit 46.
Is the voltage above 10.0 volts?All
Ye s®Test Complete.
No®Repair the open fused B (+) circuit.
Perform Verification Test VER-2A.
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Symptom:
*(NO RESPONSE(CONDITION
POSSIBLE CAUSES
IGNITION NOT ON
DIAGNOSTIC READ-OUT BOX ADAPTER CABLE DEFECTIVE
FUEL PUMP DEFECTIVE
FUSED IGNITION SWITCH OUTPUT CIRCUIT OPEN
PCM GROUNDS OPEN
FUEL PUMP RELAY OUT CKT INTERMITTENT SHORT TO GRND
FUEL PUMP RELAY OUTPUT CIRCUIT SHORT TO GROUND
SCI RECEIVE CIRCUIT OPEN
SCI RECEIVE CIRCUIT SHORT TO GROUND
SCI TRANSMIT CIRCUIT OPEN
SCI TRANSMIT CIRCUIT SHORTED TO GROUND
FUSED B(+) CIRCUIT OPEN BETWEEN FUSE AND BATTERY
DIAGNOSTIC READ-OUT BOX DEFECTIVE
PCM DEFECTIVE (NO RESPONSE)
FUSED B(+) CIRCUIT OPEN BETWEEN FUSE AND PCM
FUSED B(+) CIRCUIT SHORT TO GROUND
TEST ACTION APPLICABILITY
1 Attempt to start vehicle.
Does the vehicle start?All
Ye s®Go To 2
No®Go To 12
2 Was the Ignition on when the ªNo Responseº message was displayed? All
Ye s®Go To 3
No®Turn the ignition on to get a response.
3 Ignition off.
Using an Ohmmeter, measure the DLC ground circuit (terminals 4 and 5) to ground.
Is the resistance below 5.0 ohms for each measurement?All
Ye s®Go To 4
No®Repair the open ground circuit(s).
Perform Powertrain Verification Test VER-1A.
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TEST ACTION APPLICABILITY
9 Ignition Off.
Connect the DRB to a functional Data Link Connector on another vehicle.
Turn the ignition on.
With the DRB, attempt to read trouble codes.
Did the DRB display ªNo Responseº?All
Ye s®Go To 10
No®Replace the initial vehicle's Powertrain Control Module.
Perform Powertrain Verification Test VER-1A.
10 Ignition Off.
Substitute another DRB Adapter Cable.
Ignition on, Engine not running.
With the DRB, attempt to read trouble codes.
Did the DRB display ªNo Responseº?All
Ye s®Go To 11
No®Replace the DRB Adapter Cable.
Perform Powertrain Verification Test VER-1A.
11 If there are no potential causes remaining, the Diagnostic Readout Box is assumed to
be defective.
View repair options.All
Repair
Have the DRB repaired or replaced.
Perform Powertrain Verification Test VER-1A.
12 Ignition Off.
Disconnect the TP Sensor Connector.
Note: Check connector-Clean/repair as necessary.
Turn the ignition on.
With a voltage, measure the Throttle Position Sensor 5±volt Supply circuit.
Is the voltage above 6.0 volts?All
Ye s®Repair the open grounds at the Powertrain Control Module
Cavities 10 and 50.
Perform the Powertrain Verification Test VER-1A
No®Go To 13
13 Ignition Off.
Disconnect the Powertrain Control Module.
Note: Check connector-Clean/repair as necessary.
Turn the ignition on.
With a voltmeter, measure Fused Ignition Switch Output Circuit.
Is the voltage above 10.0 volts?All
Ye s®Go To 14
No®Repair the open Fused Ignition Switch Output Circuit (check
Ignition Switch Fuse in PDC).
Perform Powertrain Verification Test VER-1A.
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STARTING
*(NO RESPONSE(CONDITION ÐContinued
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