P1423 — Intake Air High Pressure Switch Circuit High Voltage

What Does P1423 Mean?

P1423 is a manufacturer-specific diagnostic trouble code: Intake Air High Pressure Switch Circuit High Voltage. This code applies to BUICK, CADILLAC, CHEVY, CHRYSLER, GM 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 P1423

⚠️ Check Engine Light (MIL) illuminated
⚠️ Intake Air High Pressure Switch reading stuck at maximum value
⚠️ Related system operating erratically or in default mode
⚠️ Reduced engine performance

Common Causes

🔍 Short to voltage in Intake Air High Pressure Switch wiring harness
🔍 Corroded or water-damaged Intake Air High Pressure Switch connector
🔍 Faulty Intake Air High Pressure Switch outputting maximum voltage
🔍 Damaged wiring rubbing against metal components
🔍 ECM/PCM internal fault (rare)

Frequently Asked Questions

What does P1423 mean?

P1423 indicates: Intake Air High Pressure Switch Circuit High Voltage. The vehicle's computer has detected that the Intake Air High Pressure Switch is not operating within its expected parameters and stored this diagnostic trouble code.

Can I drive with code P1423?

You can drive short distances for essential trips, but schedule a diagnosis soon. Driving with P1423 for extended periods may cause additional problems.

How much does it cost to fix P1423?

Repair costs for P1423 typically range from $20 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 and repair Intake Air High Pressure Switch wiring for short to voltage
🔧 Clean or replace corroded Intake Air High Pressure Switch connector
🔧 Replace faulty Intake Air High Pressure Switch

1
Find your vehicle above
Click your make and model for real owner reports and common causes specific to your vehicle.
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.

P1423: Intake Air High Pressure Switch Circuit High Voltage