P0754

What it means

P0754 is the generic code for an intermittent fault in the shift solenoid A circuit. The transmission control unit saw the solenoid's electrical circuit drop out, or give an implausible reading, only at times rather than constantly. Which gear or gears solenoid A controls depends on the make, model and gearbox, so check the manufacturer's data for the vehicle.

Symptoms

• Gearbox occasionally refuses to change gear or changes at the wrong time
• Harsh, flared or delayed shifts that come and go
• Car stuck in one gear (limp mode) at times
• Gearbox warning light or malfunction lamp on
• Poorer fuel economy
• Fault appears after hot running, bumps or damp weather, then clears

Possible causes

• Loose, corroded or damaged connector at the gearbox or control unitlikely
• Chafed, broken or intermittently open-circuit wiring to shift solenoid Alikely
• Internal wiring loom fault inside the gearboxpossible
• Shift solenoid A failing internally (intermittent open or short winding)possible
• Contaminated or low transmission fluid affecting the solenoid or valve bodypossible
• Low battery or supply voltage, or poor earth connectionspossible
• Fault in the transmission control unitrare

How to diagnose

1. Read all stored and pending codes and note the freeze frame data, including temperature, speed and gear, to see when the fault occurs
2. Check the battery condition and charging voltage, as low voltage can upset solenoid circuits
3. Check transmission fluid level, condition and smell, following the manufacturer's procedure for that gearbox
4. Inspect the wiring and connectors between the gearbox and control unit for chafing, water ingress, corrosion and bent or pushed-back pins
5. Wiggle test the harness and connector with the engine running or with live data on, watching for the fault setting or the solenoid state dropping out
6. Measure solenoid A resistance and compare it with the manufacturer's specification, and check the circuit for shorts to earth or supply
7. Check for relevant technical service bulletins and control unit software updates for the model
8. Check the internal gearbox harness and solenoid once the earlier checks have not found the fault

How to fix

• Clean, repair or replace the affected connector terminals or connector
• Repair or replace the damaged wiring section, using proper soldered or crimped and sealed joins
• Replace shift solenoid A or the internal harness if testing shows it is faulty
• Correct the fluid level or replace the fluid and filter if it is contaminated or degraded, as the manufacturer specifies
• Repair the battery, charging or earth fault if voltage is the cause
• Update or replace the control unit only if testing confirms a fault, or if an outdated calibration is a known cause for that model

Can I keep driving?

Nearby codes

• P0753GenericShift Solenoid A Electrical
• P0755GenericShift Solenoid B