P0378 Toyota Timing Reference High Resolution Signal B Intermittent/Erratic Pulses
Possible causes
– Timing Reference Optical Sensor harness is open or shorted
– Timing Reference Optical Sensor circuit poor electrical connection
– Faulty Timing Reference Optical Sensor
– Damaged Powertrain Control Module (PCM)
– Timing Reference Optical Sensor circuit poor electrical connection
– Faulty Timing Reference Optical Sensor
– Damaged Powertrain Control Module (PCM)
What about the obd code?
Some high resolution pulses are intermittent from the optical sensor to the PCM
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
P0378 Toyota Description
The optical sensor provides a high resolution signal to the Powertrain Control Module (PCM) by counting pulses on the sensor disk located in the injection pump. The high resolution is one of the most important inputs by the PCM for fuel control and timing. This test monitors the number of high resolution pulses which have been missed (not detected). It’s based on a comparison between the number of pulses that were detected since the last pump cam pulse and the number of the pulses that should have occurred. There are approximately 64 high resolution pulses for every cam pulse.
Toyota Vehicle:Toyota Prius,Toyota Celica,Toyota Supra,Toyota Carina,Toyota Camry,Toyota MR2,Toyota Aygo,Toyota 4Runner,Toyota Avalon,Toyota Camry,Toyota Corolla,Toyota FJ Cruiser,Toyota Highlander,Toyota Land Cruiser,Toyota Matrix,Toyota Prius,Toyota RAV4,Toyota Sequoia,Toyota Sienna,Toyota Solara,Toyota Tacoma,Toyota Tundra,Toyota Yaris,