P1874 — Transmission Automatic Hall Effect Sensor Power Circuit Failure

What Does P1874 Mean?

P1874 is a manufacturer-specific diagnostic trouble code: Transmission Automatic Hall Effect Sensor Power Circuit Failure. This code applies to OTHER, BUICK, CADILLAC, CHEVY, 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 P1874

⚠️ Check Engine Light (MIL) illuminated
⚠️ Erratic Transmission Automatic Hall Effect Sensor Power readings
⚠️ Related system operating intermittently
⚠️ Reduced engine performance

Common Causes

🔍 Wiring issue in Transmission Automatic Hall Effect Sensor Power circuit (damaged, chafed, or corroded)
🔍 Faulty Transmission Automatic Hall Effect Sensor Power connector or terminal
🔍 Failed Transmission Automatic Hall Effect Sensor Power
🔍 ECM/PCM connection issue

Frequently Asked Questions

What does P1874 mean?

P1874 indicates: Transmission Automatic Hall Effect Sensor Power Circuit Failure. The vehicle's computer has detected that the Transmission Automatic Hall Effect Sensor Power is not operating within its expected parameters and stored this diagnostic trouble code.

Can I drive with code P1874?

You can drive short distances for essential trips, but schedule a diagnosis soon. Driving with P1874 for extended periods may cause additional problems.

How much does it cost to fix P1874?

Repair costs for P1874 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 and repair Transmission Automatic Hall Effect Sensor Power wiring and connectors
🔧 Replace faulty Transmission Automatic Hall Effect Sensor Power

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.

P1874: Transmission Automatic Hall Effect Sensor Power Circuit Failure