P1934 Code - Fuel Additive Pump Control Circuit High
Quick Answer
The Fuel Additive Pump is a positive displacement pump (reciprocating pump) and, in response to commands from the fuel additive control unit, delivers a metered quantity of fuel additive to the injector on the top of the fuel tank via a short fuel pipe; the injector then injects the additive into the fuel tank. Common causes include Faulty Fuel Additive Level Pump, Fuel Additive Level Pump harness is open or shorted, Fuel Additive Level Pump circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P1934 indicates Fuel Additive Pump Control Circuit High.
- Common causes
- Common causes include Faulty Fuel Additive Level Pump, Fuel Additive Level Pump harness is open or shorted, Fuel Additive Level Pump circuit poor electrical connection.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code P1934 Description
The piezo sensor on the Fuel Additive Pump records the fill level of the fuel additive in the fuel additive tank and transmits this information to the fuel additive control unit.
Its other task is to determine any change in the viscosity of the fuel additive as a function of ambient temperatures; this may result in the metered quantity of fuel additive having to be corrected.
If the fill level of the fuel additive in the fuel additive tank falls below a certain limit, the engine system fault warning lamp in the instrument cluster will switch on.
If the fuel additive tank becomes empty, the Malfunction Indicator Lamp (MIL) will light up.
What are the Possible Causes of the DTC P1934?
- Faulty Fuel Additive Level Pump
- Fuel Additive Level Pump harness is open or shorted
- Fuel Additive Level Pump circuit poor electrical connection
How to Fix the DTC P1934?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P1934 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Information for Specific Makes
- P1934 Ford — Fuel Additive Pump Control Circuit High
- P1934 Lincoln — Fuel Additive Pump Control Circuit High
- P1934 Mazda — Fuel Additive Pump Control Circuit High
- P1934 Mercury — Fuel Additive Pump Control Circuit High
Frequently Asked Questions about P1934 Code
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