P1393 Isuzu Code – Diagnosis and Solutions

Meaning of Isuzu P1393 Code

The P1393 code on Isuzu vehicles typically indicates a problem with the crankshaft position (CKP) system, often related to an unperformed learning procedure or a faulty sensor.

Specific Interpretation

In Isuzu (often sharing GM technology), P1393 typically means:
“Crankshaft Position System Variation Not Learned”

Probable Causes

1. Unperformed learning procedure after replacing the CKP sensor or ECU
2. Faulty crankshaft position sensor (CKP)
3. Wiring problems (short circuits, breaks, corrosion)
4. Faulty flywheel (damaged teeth)
5. Engine timing problem
6. ECU failure (less common)

Common Symptoms

• Starting difficulty
• Unstable idle
• Loss of power
• Intermittent stalling
• Check engine light on

Diagnostic Procedure

1. Check the CKP sensor:

• Measure resistance (check specific values)
• Visual inspection
• Test signal with oscilloscope

2. Inspect wiring:

• Check continuity between sensor and ECU
• Look for short circuits to ground

3. Check flywheel:

• Check tooth condition
• Look for physical damage

4. Perform learning procedure:

• Requires compatible Isuzu diagnostic tool

Recommended Solutions

1. Perform CKP learning procedure (with scan tool)
2. Replace CKP sensor if faulty
3. Repair wiring if necessary
4. Check engine timing
5. Replace flywheel if teeth are damaged

Affected Isuzu Models

This code may appear on various Isuzu models, including:

• D-Max
• Rodeo
• Trooper
• NPR (diesel versions)
• Other models sharing GM platform

Important note: The exact reset procedure may vary depending on model and year. A professional diagnostic tool is often required to properly perform the CKP system learning.