P1357 — Ignition Diagnostic Monitor Pulsewidth Not Defined

What Does P1357 Mean?

P1357 is a manufacturer-specific diagnostic trouble code: Ignition Diagnostic Monitor Pulsewidth Not Defined. This code applies to FORD, LINCOLN, MERCURY, BUICK, CADILLAC vehicles. Unlike generic OBD-II codes, manufacturer-specific codes are defined by the vehicle maker and may only apply to certain makes and models.

Symptoms of P1357

⚠️ Check Engine Light (MIL) illuminated
⚠️ Ignition Diagnostic Monitor Pulsewidth Not Defined not functioning as expected
⚠️ Related system may be in fail-safe mode
⚠️ Reduced engine performance

Common Causes

🔍 Faulty Ignition Diagnostic Monitor Pulsewidth Not Defined
🔍 Wiring or connector issue in Ignition Diagnostic Monitor Pulsewidth Not Defined circuit
🔍 Related mechanical or electrical fault
🔍 ECM/PCM issue (rare)

Frequently Asked Questions

What does P1357 mean?

P1357 indicates: Ignition Diagnostic Monitor Pulsewidth Not Defined. The vehicle's computer has detected that the Ignition Diagnostic Monitor Pulsewidth Not Defined is not operating within its expected parameters and stored this diagnostic trouble code.

Can I drive with code P1357?

You can drive short distances for essential trips, but schedule a diagnosis soon. Driving with P1357 for extended periods may cause additional problems.

How much does it cost to fix P1357?

Repair costs for P1357 typically range from $80 to $300, depending on the root cause. Simple wiring or connector repairs are on the lower end, while component replacement costs more. A proper diagnosis ($80–$150 at most shops) will identify the exact cause before committing to expensive parts.

What To Do Next

Possible Fixes

🔧 Inspect Ignition Diagnostic Monitor Pulsewidth Not Defined and related wiring
🔧 Replace faulty Ignition Diagnostic Monitor Pulsewidth Not Defined

1
Find your vehicle above
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2
Check for recalls
Go to nhtsa.gov/recalls and enter your VIN. Free repairs if covered.
3
Get a professional diagnosis
A code alone doesn't identify the exact failed part. A diagnostic ($50–$150) pinpoints the root cause.

P1357: Ignition Diagnostic Monitor Pulsewidth Not Defined