Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSISUZU2004ASCENDER 2WD L6-4.2LREPAIR AND DIAGNOSISPOWERTRAIN MANAGEMENTCOMPUTERS AND CONTROL SYSTEMSTESTING AND INSPECTIONCOMPONENT TESTS AND GENERAL DIAGNOSTICSIGNITION SYSTEM DIAGNOSIS
2004 Isuzu Ascender 2WD L6-4.2L
Ignition System Diagnosis
2004 Isuzu Ascender 2WD L6-4.2LSECTION Ignition System Diagnosis
Electronic Ignition (EI) System Diagnosis
Circuit Description
The electronic ignition system uses an individual ignition coil for each cylinder. The powertrain control module (PCM) controls the ignition operation through six ignition control (IC) circuits. Each ignition coil is connected to the PCM, power, or ground by the following circuits:
- The ground
- The ignition 1 voltage
- The appropriate IC control circuit
The PCM triggers an ignition coil by grounding the appropriate IC control circuit using information from the crankshaft position (CKP) and camshaft position (CMP) sensors.
Diagnostic Aids
- The crankshaft position (CKP) signal is not needed to start and run.
- Many situations may lead to an intermittent condition. Perform each inspection or test as directed.
Important: Remove any debris from the connector surfaces before servicing a component Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion.
- Inspect the PCM and the engine grounds for clean and secure connections. Refer to Wiring Repairs in Wiring Systems.
- For intermittent conditions, refer to Intermittent Conditions.
Test Description
The number below refers to the step number on the diagnostic table.
5 A few sparks, then nothing is considered no spark.
Step 1 - 6:
Step 7 - 11:
Step 12 - 16:
Step 17 - 22:
RENDER: 1.0x
NO RELATED
Recommended Tools & Savings
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.