Damaged, chafed or corroded wiring on the communication circuit, shorted to ground; Water ingress, corrosion or loose terminals at the range control module or related connectors; Low battery voltage or poor power and earth supply to the range control module; Faulty transmission range control module pulling the circuit low internally; Another module on the same network faulty and dragging the data line low; Outdated or faulty module software, where the manufacturer has identified it as a known cause for the model.

P07F3

Transmission Range Control Module Communication Circuit Low.

Generic
Powertrain
Generic code
Medium severity

How this code is built

P: SystemPowertrain
0: Defined bySAE, the same on every car
7: AreaTransmission
F3: FaultThe specific fault in that area

What it means

P07F3 means the control unit saw the communication circuit to the transmission range control module (the module that reads and acts on the gear selector position) sitting at a lower voltage than expected. This is a data link fault, not a mechanical gearbox fault. It is usually set when the signal is pulled low by a short to ground, a wiring or connector problem, or a fault in a module on the circuit.

Symptoms

Gearbox warning light or general fault light on the dash
Gear position indicator wrong, flickering or blank
Gearbox stuck in one gear or in limp mode
Car slow to select drive or reverse, or will not shift as expected
Engine will not start, or starts only in certain selector positions
Other communication fault codes stored alongside it

Possible causes

Damaged, chafed or corroded wiring on the communication circuit, shorted to groundlikely
Water ingress, corrosion or loose terminals at the range control module or related connectorslikely
Low battery voltage or poor power and earth supply to the range control modulepossible
Faulty transmission range control module pulling the circuit low internallypossible
Another module on the same network faulty and dragging the data line lowpossible
Outdated or faulty module software, where the manufacturer has identified it as a known cause for the modelrare

How to diagnose

Read all stored and pending codes and the freeze frame data, noting whether other network or module communication codes are present
Check battery condition and charging voltage, as low voltage can cause false communication faults
Visually inspect the wiring, connectors and mounting area of the range control module for damage, rubbing, corrosion or moisture
Check the fuses and the power and earth supplies to the range control module against the wiring diagram for that model
With the ignition off and the battery disconnected, test the communication circuit for a short to ground and check its resistance against the manufacturer's specification
Check live data to see whether the range control module is communicating and whether the selector position changes are shown correctly
Unplug other modules on the same network one at a time, following the manufacturer's procedure, to see if the low signal clears
Check for software updates or technical bulletins applicable to the vehicle and module

How to fix

Repair or replace damaged wiring and fix any short to ground on the communication circuit
Clean, dry and repair or replace corroded or loose connectors and terminals
Restore a good power and earth supply, and repair or replace a weak battery or charging fault
Replace a confirmed faulty transmission range control module, and code or program it to the vehicle as required
Replace any other faulty module found to be pulling the network low
Apply a manufacturer calibration update only where an outdated calibration is a known cause for that model

Can I keep driving?

Medium severity

The car may be driveable, but gear selection or starting could become unreliable or the gearbox may drop into limp mode, so get it checked soon. Stop driving if you cannot reliably select gears or park.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.