P07F5

What it means

P07F5 means the transmission range control module (the unit that manages gear range selection, often on shift-by-wire or electronic selector systems) has detected its supply voltage below the expected minimum. The module monitors its own power feed and sets this code when the voltage drops under the calibrated threshold for long enough. The exact threshold and the way the module is powered depend on the vehicle and transmission.

Symptoms

• Gearbox or transmission warning light on the dashboard
• Selector not responding or slow to change range (for example Park, Reverse, Drive)
• Transmission stuck in one gear or in a limp-home mode
• Engine slow to crank or other low-voltage warnings and messages
• Intermittent fault that appears after short journeys or when electrical loads are high
• Car will not shift out of Park or will not engage Park properly

Possible causes

• Weak, discharged or ageing 12 V batterylikely
• Corroded, loose or damaged battery terminals or earth connectionslikely
• High resistance in the module's power supply circuit, such as a poor connector, damaged wiring or a faulty fuse or relay contactlikely
• Charging system fault, such as a failing alternator or regulator, causing low system voltagepossible
• Water ingress or corrosion in the module connector or at the selector or transmission harnesspossible
• Internal fault in the transmission range control module affecting its voltage monitoring or supplyrare

How to diagnose

1. Read all stored and pending codes and the freeze frame data, noting battery voltage, vehicle speed and engine state when the code set; check for other low-voltage or communication codes
2. Measure resting battery voltage and carry out a battery load or conductivity test to judge battery health
3. Inspect battery terminals, main earths and the engine-to-body earth strap for corrosion, looseness or damage
4. Check charging output with the engine running and with electrical loads on, and compare it against the manufacturer's specification
5. Check the fuses and relays that feed the range control module, using the wiring diagram for that model, and look for heat marks or poor contact
6. Inspect the module and selector connectors and harness for moisture, green corrosion, bent pins or chafing
7. Voltage drop test the module's power and earth circuits while it is operating, following the manufacturer's procedure
8. Clear the code and road test, rechecking for return; if the supply tests good and the code returns, consider module diagnosis per the manufacturer's procedure

How to fix

• Recharge or replace the 12 V battery and confirm the vehicle's charging and battery registration needs for that model
• Clean and tighten battery terminals and earth points, repairing or replacing any damaged leads
• Repair or replace damaged wiring, corroded connectors or faulty fuse and relay contacts in the module's supply circuit
• Repair or replace the alternator or regulator if the charging output is out of specification
• Dry out, clean and reseal the affected connectors, and fix the source of any water ingress
• Replace or reprogram the transmission range control module only after supply and earth faults are ruled out and a fault in the module is confirmed

Can I keep driving?

Nearby codes

• P07F4GenericTransmission Range Control Module Communication Circuit High
• P07F6GenericGear 9 Incorrect Ratio