P2A79 — Alternative Fuel Hydraulic Pump Pressure Sensor Circuit Intermittent/Erratic

What Does P2A79 Mean?

P2A79 is a diagnostic trouble code indicating: Alternative Fuel Hydraulic Pump Pressure Sensor Circuit Intermittent/Erratic. This code relates to the vehicle systems system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.

Symptoms of P2A79

⚠️ Check Engine Light (MIL) illuminated
⚠️ Alternative Fuel Hydraulic Pump Pressure Sensor signal cutting in and out
⚠️ Related system working sometimes but not consistently
⚠️ System warning light illuminated

Common Causes

🔍 Loose or intermittent connection at Alternative Fuel Hydraulic Pump Pressure Sensor
🔍 Wire chafing causing intermittent contact
🔍 Alternative Fuel Hydraulic Pump Pressure Sensor failing under heat or vibration
🔍 Corroded connector pins with partial contact

Frequently Asked Questions

What does P2A79 mean?

P2A79 indicates: Alternative Fuel Hydraulic Pump Pressure Sensor Circuit Intermittent/Erratic. The vehicle's computer has detected that the Alternative Fuel Hydraulic Pump Pressure Sensor is not operating within its expected parameters and stored this diagnostic trouble code.

Can I drive with code P2A79?

Yes, P2A79 is generally safe to drive with in the short term. However, it should still be addressed to pass emissions testing and prevent potential secondary issues.

How much does it cost to fix P2A79?

Repair costs for P2A79 typically range from $30 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 reseat all Alternative Fuel Hydraulic Pump Pressure Sensor connectors
🔧 Repair chafed or damaged wiring in Alternative Fuel Hydraulic Pump Pressure Sensor circuit
🔧 Replace Alternative Fuel Hydraulic Pump Pressure Sensor if failing intermittently

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.

P2A79: Alternative Fuel Hydraulic Pump Pressure Sensor Circuit Intermittent/Erratic