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Jeep Wrangler TJ. Manual - part 133

POSSIBLE CAUSES

GOOD TRIP EQUAL TO ZERO

EXHAUST LEAK

ENGINE MECHANICAL PROBLEM

O2 SENSOR

O2 SIGNAL CIRCUIT

O2 RETURN CIRCUIT

FUEL CONTAMINATION

TEST

ACTION

APPLICABILITY

NOTE: Check the vehicle repair history. If the O2 has been replace ensure
that the O2 sensor was properly installed and meets OEM specification.
NOTE: Check for contaminants that may have damaged the O2 Sensor:
contaminated fuel, unapproved silicone, oil and coolant.
Ignition on, engine not running.
With the DRBIII

t, read DTCs and record the related Freeze Frame data.

Is the Good Trip Counter displayed and equal to zero?

All

Yes

→ Go To 2

→ Refer to the INTERMITTENT CONDITION symptom in the

Driveability category.
Perform POWERTRAIN VERIFICATION TEST VER - 5.

Turn the ignition off.
WARNING: To avoid personal injury from the exhaust system being hot,
allow the exhaust to cool down to a safe temperature before performing a
physical inspection.
Visually and Physically inspect the for holes, cracks and blockage in the exhaust
system.
Is the exhaust system is good condition?

All

Yes

→ Go To 3

→ Repair or Replace as necessary.

Perform POWERTRAIN VERIFICATION TEST VER - 5.

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P2096-DOWN STREAM FUEL TRIM LEAN BANK 1 —

Continued

TEST

ACTION

APPLICABILITY

Check for any of the following conditions/mechanical problems.
AIR INDUCTION SYSTEM - must be free from leaks.
ENGINE VACUUM - must be at least 13 inches in neutral
ENGINE VALVE TIMING - must be within specifications
ENGINE COMPRESSION - must be within specifications
ENGINE EXHAUST SYSTEM - must be free of any restrictions or leaks.
ENGINE PCV SYSTEM - must flow freely
TORQUE CONVERTER STALL SPEED - must be within specifications
POWER BRAKE BOOSTER - no internal vacuum leaks
FUEL - must be free of contamination
FUEL INJECTOR - plugged or restricted injector; control wire not connected to
correct injector
Are there any engine mechanical problems?

All

Yes

→ Repair as necessary.

Perform POWERTRAIN VERIFICATION TEST VER - 5.

→ Go To 4

Ignition on, engine not running.
Disconnect the O2 Sensor harness connector.
With the DRBIII

t, monitor the O2 Sensor voltage.

The O2 Sensor voltage should read 5.0 volts on the DRBIII

t with the connector

disconnected.
Using a jumper wire, jump the O2 Signal circuit to the O2 Return circuit in the O2
Sensor harness connector.
NOTE: The voltage should drop from 5.0 volts to 2.5 volts with the jumper
wire in place.
Did the O2 Sensor volts change from 5.0 volts to 2.5 volts?

All

Yes

→ Replace the O2 Sensor

Perform POWERTRAIN VERIFICATION TEST VER - 5.

→ Go To 5

Remove the jump wire.
Ignition on, engine not running.
With the DRBIII

t, monitor the O2 Sensor voltage.

Is the voltage above 4.8 volts?

All

Yes

→ Go To 6

→ Check the O2 Signal circuit for a short to ground, open, or short

to voltage. Inspect the O2 Sensor connector and the PCM harness
connector. If OK, replace and program the Powertrain Control
Module in accordance with the Service Information.
Perform POWERTRAIN VERIFICATION TEST VER - 5.

Measure the voltage on the O2 Return circuit in the O2 Sensor harness connector.
Is the voltage at 2.5 volts?

All

Yes

→ Check the fuel system for contaminants.

Perform POWERTRAIN VERIFICATION TEST VER - 5.

→ Check the O2 Return circuit for a short to ground, open, or short

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DRIVEABILITY - NGC

P2096-DOWN STREAM FUEL TRIM LEAN BANK 1 —

Continued

Symptom List:

P2302-IGNITION COIL NO.1 SECONDARY CIRCUIT- INSUFFI-
CIENT IONIZATION
P2305-IGNITION COIL NO.2 SECONDARY CIRCUIT- INSUFFI-
CIENT IONIZATION
P2308-IGNITION COIL NO.3 SECONDARY CIRCUIT- INSUFFI-
CIENT IONIZATION

Test Note:

All symptoms listed above are diagnosed using the same tests.

The title for the tests will be P2302-IGNITION COIL NO.1
SECONDARY CIRCUIT- INSUFFICIENT IONIZATION.

When Monitored and Set Condition:

P2302-IGNITION COIL NO.1 SECONDARY CIRCUIT- INSUFFICIENT IONIZA-
TION

When Monitored:

Engine running and battery voltage greater than 10 volts.

Set Condition:

If PCM detects that the secondary ignition burn time is incorrect or not

present an error is detected. One Trip Fault. Three good trips to turn off the MIL.

P2305-IGNITION COIL NO.2 SECONDARY CIRCUIT- INSUFFICIENT IONIZA-
TION

When Monitored:

Engine running and battery voltage greater than 10 volts.

Set Condition:

If PCM detects that the secondary ignition burn time is incorrect or not

present an error is detected. One Trip Fault. Three good trips to turn off the MIL.

P2308-IGNITION COIL NO.3 SECONDARY CIRCUIT- INSUFFICIENT IONIZA-
TION

When Monitored:

Engine running and battery voltage greater than 10 volts.

Set Condition:

If PCM detects that the secondary ignition burn time is incorrect, to short,

or not present, an error is detected. One Trip Fault. Three good trips to turn off the MIL.

POSSIBLE CAUSES

GOOD TRIP EQUAL TO ZERO

(K334) ASD RELAY OUTPUT CIRCUIT

COIL RAIL RESISTANCE

IGNITION COIL

IGNITION COIL DRIVER CIRCUIT OPEN

IGNITION COIL DRIVER CIRCUIT SHORTED TO GROUND

PCM

259

DRIVEABILITY - NGC

TEST

ACTION

APPLICABILITY

Check for any related TSBs.
Ignition on, engine not running.
With the DRBIII

t, read DTCs and record the related Freeze Frame data.

Is the Good Trip Counter displayed and equal to zero?

All

Yes

→ Go To 2

→ Refer to the INTERMITTENT CONDITION Symptom (Diagnos-

tic Procedure).
Perform POWERTRAIN VERIFICATION TEST VER - 5.

Turn the ignition off.
Disconnect the coil rail harness connector.
Ignition on, engine not running.
With the DRBIII

t, actuate the ASD Relay.

Using a 12-volt test light connected to ground, check the (K334) ASD Relay Output
circuit at the coil rail harness connector.
Does the test light illuminate brightly?

All

Yes

→ Go To 3

→ Repair the excessive resistance or short to ground in the (K334

ASD Relay Output circuit. Inspect the related fuse and repair as
necessary.
Perform POWERTRAIN VERIFICATION TEST VER - 5.

Stop All Actuations

Turn the ignition off.
Disconnect the coil rail harness connector.
Note: The following resistance measurement should be taken at 70-80
degrees F.
NOTE: The resistance of the 2.4L Primary Ignition Coil is 0.53 to 0.63 of an
ohm and the resistance of a 4.0L Primary Coil Rail is 0.51 to 0.61 of an ohm
at 70°F (21.1°C).
Measure the resistance of the Primary Coil Rail.
Is the resistance value within the noted specification for the coil being tested?

All

Yes

→ Go To 4

→ Replace the coil rail.

Perform POWERTRAIN VERIFICATION TEST VER - 5.

Turn the ignition off.
Disconnect the Ignition Coil Rail harness connector.
Using a 12-volt test light connected to a 12-volt source, probe the Ignition Coil Driver
circuit.
Crank the engine for 5 seconds while observing the test light.
Does the test light blink/flicker?

All

Brightly blinking or flickering.

Replace the Ignition Coil Rail.
Perform POWERTRAIN VERIFICATION TEST VER - 5.

ON constantly.

Go To

OFF constantly.

Go To

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DRIVEABILITY - NGC

P2302-IGNITION COIL NO.1 SECONDARY CIRCUIT- INSUFFICIENT
IONIZATION —

Continued

Content .. 131 132 133 134 ..