TFI Module Failure Ford TP 31 Ford TFI Module Failure Today's electronic components are very reliable. Most failures are caused by other problems. Anytime a Ford TFI module is diagnosed as having failed, several steps should be followed: 1. Verify charging system operation; specifically, charging voltage. 2. Verify ignition system operation; specifically, there are no open or disconnected plug wires. 3. Remove distributor cap and inspect connections where TFI module hooks to the Hall Effect Switch connector. If there is any sign of deterioration at the connector, the Hall Effect pickup must be replaced. Crankcase vapors are forced into the distributor due to excessive crankcase pressure due to a worn engine or an improperly maintained PCV system. The crankcase vapors cause deterioration of the insulation around the connectors causing the module to short out. Visit our Resource Library for available downloads