Isuzu 2000 Trooper Workshop Manual page 1168

Diagnostic Aids
Check for the following conditions:
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 the
Step
1 Was the "On-Board Diagnostic (OBD) System Check"
performed?
2 1. Ignition "ON," engine "OFF."
2. Review and record Tech 2 Failure Records data.
3. Operate the
conditions as noted.
4. Use a Tech 2 to monitor the "DTC" information for
DTC P0353 until the DTC P0353 test runs.
5. Note the test result.
Does the Tech 2 indicate DTC P0353 failed this ignition
cycle?
3 Check for faulty connection at ignition coil.
Was a problem found?
4 Check for faulty connection at PCM connector.
Was a problem found?
5 1. Ignition "ON," engine "OFF."
2. Back probe the ignition control circuit 3 at the ION
Sensing Module with a DVM positive lead with the
negative lead to ground.
Is the voltage near the specified value?
6 1. Ignition "ON," engine running.
2. Back probe the ignition control circuit at the ION
Sensing Module for the cylinder being tested.
Is the voltage in the specified range, rapidly toggling
back and forth to a reading 20-50 mV higher?
7 1. Ignition "OFF."
2. Disconnect the 3-pin connector at the ignition coil.
3. Check ignition control circuit 3 voltage at the ignition
coil connector while cranking the engine.
Does the voltage measure between the specified
values?
8 Replace the ignition coil.
Is the action complete?
9 1. Ignition "OFF."
2. Disconnect the PCM and the ignition coil.
3. Check ignition control circuit 3 for short to ground.
Was a problem found?
10 Check ignition control circuit 3 for short to voltage.
Was a problem found?
TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0353 – Ignition 3 Control Circuit
Action
vehicle within Failure
Tech 2 display related to DTC P0353 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.
Value(s)
—
Record
—
—
—
25-55 mV
100-180 mV
200-1200 mV
—
—
—
6E–299
Yes No
Go to OBD
System
Check
Go to Step 2
Go to
Diagnostic
Go to Step 3 Aids
Verify repair Go to Step 4
Go to Step 5
Verify repair
Go to Step 6 Go to Step 9
Go to Step 7 Go to Step 13
Go to Step 8 Go to Step 11
Verify repair —
Verify repair Go to Step 10
Verify repair Go to Step 13