P2768 Intermittent Circuit of Input/Turbine Speed Sensor B

Symptoms

Symptoms of a P2768 code may include:

Erratic operation of the speedometer (odometer)
Transmission not functioning properly
The speedometer and/or odometer will not work at all
Transmission shift points are irregular or harsh
Reduced fuel efficiency

Causes

Potential causes for setting this code are as follows:

Faulty input speed sensor B
Damaged, loose, or burnt wiring and/or connectors
PCM failure or PCM programming error
Accumulation of metallic debris on the magnetic sensor

Diagnostic and Repair Procedures

A good starting point is always to check the technical service bulletins (TSBs) for your specific vehicle. Your issue may be a known problem with a known fix released by the manufacturer and can save you time and money when diagnosing.

A digital volt/ohmmeter (DVOM), manufacturer’s service manual, advanced diagnostic scanner, and possibly an oscilloscope will be essential to properly diagnose the P2768 code.

I usually start my diagnosis with a visual inspection of the system’s wiring and connectors. I would repair any obviously shorted or open circuits and/or connectors before proceeding. Remember to inspect the battery, battery cables, and cable ends, and test the alternator output at this stage.

Next, I would connect the scanner to the diagnostic port and retrieve all stored codes, noting them for future reference. I would also take note of the freeze frame data at that moment.

Use the scanner’s data stream to determine which circuit is malfunctioning, if input sensor and output sensor codes are present. To get the most accurate data available with the scanner, refine the data stream to include only relevant information.

Metallic debris on the magnetic contacts of the input and/or output speed sensors can cause intermittent/erratic sensor output data. Remove the sensor and check for metallic debris. Clean excessive debris from the magnetic surfaces before reinstalling. I would also inspect the interruptor grooves and/or reluctor wheel notches for signs of damage or wear.

I use the DVOM to test the individual sensor resistance and circuit voltage following the manufacturer’s guidelines (found in the service manual or via AllData). I would replace sensors that do not meet the manufacturer’s specifications.

A controller failure can occur if all associated controllers are not disconnected before testing resistance or continuity with the DVOM.

Suspect a faulty PCM or PCM programming error if a P2768 code is recorded and all system circuits and sensors are in good working order and meet the manufacturer’s specifications.

Additional Diagnostic Notes:

Excessive metallic debris (attracted by the electromagnetic sensor) can cause erratic input/output speed sensor readings
The gap between the sensor and the reluctor is critical. Ensure that mounting surfaces/threaded holes are free of debris and obstructions
If the input and/or output speed sensors need to be removed from the transmission case, be cautious. Hot transmission fluid may leak from the opening
Look for transmission fluid in the input speed sensor connector area, as some sensors tend to leak internally

P2769 Low Torque Converter Clutch Circuit

Symptoms

Symptoms of a P2769 trouble code may include:

Malfunction Indicator Lamp (MIL) is illuminated (also known as check engine light)
Minimal decrease in fuel economy, this will not affect engine performance

Potential Causes

Causes of this DTC may include:

Damaged transmission wiring harness, loose connection, open or shorted circuit
Torque Converter Clutch (TCC) solenoid
Transmission Control Module (TCM)

Diagnostic Steps for P2769 DTC

Wiring Harness – Check that the transmission wiring harness is not damaged or loose. Use a factory wiring diagram to locate the appropriate power source and all connection points between circuits. The transmission may be powered by a fuse or relay and triggered by the TCM. Disconnect the transmission harness at the transmission connector, power source, and TCM. Check continuity within the internal transmission wiring harness by locating the appropriate + and – pins for the torque converter clutch solenoid.

Using a digital volt ohm meter (DVOM) set to ohms scale, check resistance in the circuit with positive and negative leads on the appropriate pins. If resistance is extremely high or above limit (OL), suspect internal harness or TCC solenoid failure – removal of transmission oil pan may be necessary to further diagnose TCC solenoid.

Test wiring between TCM and transmission case wiring harness connector using DVOM set to ohms. Check for possible short to ground by moving DVOM negative lead to a known good ground, resistance should be very high or above (OL).

Torque Converter Clutch (TCC) Solenoid – Check TCC solenoid and internal transmission wiring resistance at transmission case after removing transmission harness plug (if applicable, some makes/models use TCM bolted directly to transmission case). Some makes/models use transmission wiring harness with TCC solenoid and internal harness as one unit. DVOM should be set to ohms scale with positive and negative leads on TCC power and control circuit pins. Resistance should be within manufacturer specifications, if very high or above limit (OL), remove transmission oil pan to inspect solenoid inside transmission if possible. Check voltage on TCC solenoid power circuit or wiring harness connector at TCM with DVOM set to volts scale, positive lead to tested wire and negative to known good ground with vehicle key on/engine off, battery voltage should be present.

Transmission Control Module (TCM) – Since torque converter clutch only engages under certain driving conditions, it will be necessary to monitor TCM with advanced scan tool to determine if TCM is commanding TCC solenoid and what actual feedback reading is to TCM. TCC solenoid is normally controlled by duty cycle for smoother torque converter lockup engagement.

To test if TCM is actually sending signal, graphing multimeter set to duty cycle or digital storage oscilloscope will also be needed. Positive lead is probed into wiring harness plugged into TCM and negative lead to known good ground. Duty cycle should match what TCM is commanding in advanced scan tool reading. If cycle remains at 0% or 100% or is intermittent, recheck connections and if all wiring/solenoid is OK, TCM may be faulty.

P2770 – High Torque Converter Clutch Circuit

Symptoms

Symptoms of a P2770 trouble code may include:

Malfunction Indicator Lamp (MIL) is illuminated (also called check engine light)
Minimal decrease in fuel economy, this will not affect engine performance

Potential Causes

Causes of this DTC may include:

Damaged transmission wiring harness, loose connection, open or shorted circuit
Torque Converter Clutch (TCC) solenoid
Transmission Control Module (TCM)

Diagnostic Steps for P2770 DTC

Using a digital volt ohm meter (DVOM) set to the ohms scale, check the resistance in the circuit with the positive and negative leads on the appropriate pins. If the resistance is extremely high or above the limit (OL), suspect an internal harness or TCC solenoid failure – removal of the transmission oil pan may be necessary to further diagnose the TCC solenoid.

Test the wiring between the TCM and the transmission case wiring harness connector using the DVOM set to ohms. Check for possible short to ground by moving the negative DVOM lead to a known good ground, the resistance should be very high or above (OL).

Torque Converter Clutch (TCC) Solenoid – Check the resistance of the TCC solenoid and internal transmission wiring to the transmission case after removing the transmission harness plug (if applicable, some makes/models use a TCM bolted directly to the transmission case). Some makes/models use a transmission wiring harness with the TCC solenoid and internal harness as a single unit. The DVOM should be set to the ohms scale with the positive and negative leads on the TCC power and control circuit pins. The resistance should be within manufacturer specifications, if it is very high or above the limit (OL), remove the transmission oil pan to inspect the solenoid inside the transmission if possible. Check voltage on the TCC solenoid power circuit or at the wiring harness connector to the TCM with the DVOM set to the volts scale, positive lead to the tested wire and negative to a known good ground with the vehicle key on/engine off, battery voltage should be present.

Transmission Control Module (TCM) – Since the torque converter clutch is only engaged under certain driving conditions, it will be necessary to monitor the TCM with an advanced scan tool to determine if the TCM is commanding the TCC solenoid and what the actual feedback reading is to the TCM. The TCC solenoid is normally controlled by a duty cycle to provide a more comfortable torque converter lockup engagement.

To test if the TCM is actually sending the signal, a graphing multimeter set to duty cycle or a digital storage oscilloscope will also be needed. The positive lead is probed into the wiring harness plugged into the TCM and the negative lead to a known good ground. The duty cycle should match what is commanded by the TCM in the advanced scan tool reading. If the cycle remains at 0% or 100% or is intermittent, recheck connections and if all wiring/solenoid is OK, the TCM may be faulty.

Electric Car Charger Tax Credit Ends in 2026

Home Charging Stations Face New Financial Hurdle

The 2026 Finance Bill, introduced in October, includes the elimination of a 500-euro tax credit for purchasing a home electric vehicle charging station. This change may significantly slow the adoption of electric cars across France by increasing the upfront costs for potential EV owners.

Impact on Electric Vehicle Adoption

Removing this incentive could deter many consumers from transitioning to electric vehicles. The tax credit has been instrumental in offsetting the initial investment required for home charging infrastructure, making EVs more accessible to a broader audience. Without it, the total cost of owning an electric vehicle rises, potentially extending the payback period and reducing the financial appeal of going electric.

Broader Implications for Sustainable Transport

This policy shift arrives as governments worldwide are pushing for greener transportation solutions. The discontinuation of the tax credit might conflict with long-term environmental goals, such as reducing carbon emissions and improving urban air quality. It highlights the challenges in balancing budgetary constraints with the need to support emerging clean technologies.

Industry experts suggest that alternative support mechanisms, such as grants or low-interest loans, could help mitigate the impact. However, the absence of immediate replacements may create a gap in incentives, slowing down the momentum gained in recent years toward electric mobility.

Looking Ahead

As 2026 approaches, stakeholders in the automotive and energy sectors are likely to advocate for revised policies that continue to encourage EV adoption. The decision underscores the importance of stable, long-term incentives to ensure a smooth transition to sustainable transportation and avoid setbacks in achieving climate targets.

P2771 – Four-Wheel Drive Low Switch Circuit

P2771 Possible Causes

Faulty four-wheel drive low switch
Four-wheel drive low switch harness is open or shorted
Poor electrical connection in four-wheel drive switch circuit

How to Fix Code P2771

Check the “Possible Causes” listed above. Visually inspect the wiring harness and related connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

Possible Symptoms

Check engine light on (or service engine soon warning light)

P2771 Meaning

For vehicles equipped with an active transfer case, the four-wheel drive low (4WD) circuit consists of the powertrain control module (PCM), a transfer case control module, and circuit wiring. The transfer case control module controls the 4WD low signal on the signal circuit. When the operator selects 4WD low, the transfer case control module grounds the signal circuit, and the 4WD low signal voltage on the circuit changes from ignition voltage to zero volts. The PCM then compensates for the transfer case reduction ratio in the transmission output shaft speed (OSS) sensor signal. The PCM uses the transmission OSS sensor signal to adjust shift points, line pressure, and torque converter clutch (TCC) programming.

For vehicles not equipped with an active transfer case, the four-wheel drive low circuit consists of the PCM, a transfer case switch, and circuit wiring. The transfer case switch controls the 4WD low signal on the signal circuit. When the operator selects 4WD low, the transfer case switch closes and the 4WD low signal voltage on the signal circuit changes from ignition voltage to zero volts. The PCM then compensates for the transfer case reduction ratio in the transmission output shaft speed (OSS) sensor signal. The PCM uses the transmission OSS sensor signal to adjust shift points, line pressure, and TCC programming.

P2772 – Four-Wheel Drive Low Switch Circuit Range/Performance

P2772 Possible Causes

Faulty four-wheel drive low switch
Four-wheel drive low switch harness is open or shorted
Poor electrical connection in the four-wheel drive switch circuit

How to Fix Code P2772

Check the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

Possible Symptoms

Check engine light on (or service engine soon warning light)

P2772 Meaning

The Transmission Control Module (TCM) monitors the signal from the four-wheel drive low switch circuit. The TCM sets the OBDII code when the four-wheel drive low switch circuit is outside factory specifications.

P2773 – Low Four-Wheel Drive Switching Circuit Low

P2773 Possible Causes

Faulty four-wheel drive low switch
Four-wheel drive low switch harness is open or shorted
Poor electrical connection in the four-wheel drive switch circuit

How to Fix Code P2773

Possible Symptoms

Check Engine Light on (or Service Engine Soon warning light)

P2773 Meaning

P2774 – High Four-Wheel Drive Low Switching Circuit

P2774 Possible Causes

Faulty four-wheel drive low switch
Four-wheel drive low switch harness is open or shorted
Poor electrical connection in four-wheel drive switch circuit

How to Fix Code P2774

Possible Symptoms

Check Engine Light on (or Service Engine Soon warning light)

P2774 Meaning

P2775 – Shift Switch Circuit Range / Performance

P2775 Possible Causes

Faulty gear shift switch
Gear shift switch harness is open or short-circuited
Poor electrical connection in the gear shift switch circuit

How to Fix Code P2775

Possible Symptoms

Engine light on (or service engine soon warning light)

P2775 Meaning

The Engine Control Module (ECM) monitors the signal from the gear shift switch circuit. The ECM sets the OBDII code when the gear shift switch circuit signal does not meet factory specifications.

P2776 – Low Shift Switch Circuit

P2776 Possible Causes

Faulty gear shift switch
Gear shift switch harness is open or short-circuited
Poor electrical connection in the gear shift switch circuit

How to Fix Code P2776

Possible Symptoms

Check engine light on (or service engine soon warning light)

P2776 Meaning

The Engine Control Module (ECM) monitors the signal from the gear shift switch circuit. The ECM sets the OBDII code when the gear shift switch circuit signal does not meet factory specifications.