Opel Frontera UBS. Manual - part 325

6E–206

ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code (DTC) P0351 Ignition 1 Control Circuit

D06RW072

Circuit Description

The powertrain control module’s (PCM) control circuit 1
provides a zero-volt or a 5-volt output signal to the ignition
coil.  The normal voltage on the circuit is zero volts.  When
the ignition coil receives the 5-volt signal from the PCM, it
provides a ground path for the B+ supply to the primary
side of the number 1 ignition coil.  When the PCM shuts off
the 5 volts to the ignition coil, the ignition coil turns “OFF.”
This causes the ignition coil primary magnetic field to
collapse, producing a voltage in the secondary coil which
fires the spark plug.
The circuit between the PCM and ignition coil is monitored
for an open circuit, short to voltage, and short to ground.
When the PCM detects a problem on ignition control
circuit 1, it will set a DTC P0351.

Conditions for Setting the DTC

D

The ignition is “ON.”

D

The engine is turning, determined by the 58X
crankshaft position input signal.

D

The output voltage is not equal to 5 volts when output
is “ON.”

D

The output voltage is not equal to 0 volts when output
is “OFF.”

D

Twenty test failures occur within 40 samples of
continuous spark events.

Action Taken When the DTC Sets

D

The PCM will illuminate the malfunction indicator lamp
(MIL) the first time the fault is detected.

D

The PCM will store conditions which were present
when the DTC was set as Freeze Frame and in the
Failure Records data.

Conditions for Clearing the MIL/DTC

D

DTC P0351 can be cleared by using Tech 2 “Clear Info”
function or by disconnecting the PCM battery feed.

Diagnostic Aids

Check for the following conditions:

6E–207

ENGINE DRIVEABILITY AND EMISSIONS

D

Poor connection at PCM – Inspect the harness
connectors for backed-out terminals, improper mating,
broken locks, improperly formed or damaged
terminals, and poor terminal-to-wire connections.

D

Damaged harness – Inspect the wiring harness for
damage.  If the harness appears to be OK, observe
Tech 2 display related to DTC P0351 while moving the

connector and wiring related to the ignition system.  A
change in the display will indicate the location of the
fault.

Reviewing the Failure Records vehicle mileage since the
diagnostic test last failed may help determine how often
the condition that caused the DTC to be set occurs.  This
may assist in diagnosing the condition.

DTC P0351 – Ignition 1 Control Circuit

 

Step

Action

Value(s)

Yes

No

1

Was the “On-Board Diagnostic (OBD) System Check”
performed?

—

Go to 

Step 2

Go to 

OBD

System

Check

2

1. Ignition “ON,” engine “OFF.”
2. Review and record Tech 2 Failure Records data.
3. Operate the vehicle within Failure Record

conditions as noted.

4. Use Tech 2 to monitor the “Specific DTC”

information for DTC P0351 until the DTC P0351 test
runs.

5. Note the test result.

Does Tech 2 indicate DTC P0351 failed this ignition
cycle?

—

Go to 

Step 3

Go to

Diagnostic

Aids

3

Check for faulty connection at ignition coil.

Was a problem found?

—

Verify repair 

Go to 

Step 4

4

Check for faulty connection at PCM connector.

Was a problem found?

—

Verify repair 

Go to 

Step 5

5

1. Ignition “ON,” engine “OFF.”
2. Back probe the ignition control circuit 1 at the PCM

with a DVM.

Is the voltage near the specified value?

25-55 mV

Go to 

Step 6

Go to 

Step 9

6

1. Ignition “ON,” engine running.
2. Back probe the ignition control circuit at the PCM for

the cylinder being tested.

Is the voltage in the specified range, rapidly toggling
back and forth to a reading 20-50 mV higher?

100-180 mV

Go to 

Step 7

Go to 

Step 13

7

1. Ignition “OFF.”
2. Disconnect the 3-pin and 5-pin connectors at the

ignition coil.

3. Check ignition control circuit 1 voltage at the ignition

coil connector while cranking the engine.

Does the voltage measure between the specified
values?

200-1200 mV

Go to 

Step 8

Go to 

Step 11

8

Replace the ignition coil.

Is the action complete?

—

Verify repair

—

9

1. Ignition “OFF.”
2. Disconnect the PCM and the ignition coil.
3. Check ignition control circuit 1 for short to ground.

Was a problem found?

—

Verify repair 

Go to 

Step 10

10

Check ignition control circuit 1 for short to voltage.

Was a problem found?

—

Verify repair

Go to 

Step 13

6E–208

ENGINE DRIVEABILITY AND EMISSIONS

DTC P0351 – Ignition 1 Control Circuit

  (Cont'd)

Step

No

Yes

Value(s)

Action

11

Check for an open ignition control circuit 1.

Was the ignition control circuit open?

—

Go to 

Step 12

Go to 

Step 13

12

Repair the open ignition control circuit.

Is the action complete?

—

Verify repair

—

13

Replace the PCM.

IMPORTANT: The replacement PCM must be
programmed.  Refer to 

UBS 98model year Immobilizer

Workshop Manual.

Is the action complete?

—

Verify repair

—

6E–209

ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code (DTC) P0352 Ignition 2 Control Circuit

D06RW072

Circuit Description

The powertrain control module’s (PCM) control circuit 2
provides a zero-volt or a 5-volt output signal to the ignition
coil.  The normal voltage on the circuit is zero volts.  When
the ignition coil receives the 5-volt signal from the PCM, it
provides a ground path for the B+ supply to the primary
side of the number 2 ignition coil.  When the PCM shuts off
the 5 volts to the ignition coil, the ignition coil turns “OFF.”
This causes the ignition coil primary magnetic field to
collapse, producing a voltage in the secondary coil which
fires the spark plug.
The circuit between the PCM and ignition coil is monitored
for an open circuit, short to voltage, and short to ground.
When the PCM detects a problem on ignition control
circuit 2, it will set a DTC P0352.

Conditions for Setting the DTC

D

The ignition is “ON.”

D

The engine is turning, determined by the 58 X
crankshaft position input signal.

D

The output voltage is not equal to 5 volts when output
is “ON.”

D

The output voltage is not equal to 0 volts when output
is “OFF.”

D

Twenty test failures occur within 40 samples of
continuous spark events.

Action Taken When the DTC Sets

D

The PCM will illuminate the malfunction indicator lamp
(MIL) the first time the fault is detected.

D

The PCM will store conditions which were present
when the DTC was set as Freeze Frame and in the
Failure Records data.

Conditions for Clearing the MIL/DTC

D

DTC P0352 can be cleared by using the Tech 2 “Clear
Info” function or by disconnecting the PCM battery
feed.

Diagnostic Aids

Check for the following conditions: