Exam 11: Electronically Controlled Transmission

Technician A says that transmissions with an input shaft speed sensor and a Vehicle Speed Sensor (VSS) can use this information to determine shift solenoid failure. Technician B says the input shaft speed sensor may also be called a turbine speed sensor. Who is correct?

Technician A says that as soon as the brake pedal is depressed, the TCC is released to prevent drag and engine stalling. Technician B says that when the brake pedal is depressed, the PCM engages the TCC. Who is correct?

Technician A says that a TPS sensor input is used by either the PCM or the TCM. Technician B says that in a modern fly by wire vehicle, there are at least two, possibly three, TPS sensors that report throttle position. Who is correct?

Which of the following provides input shaft speed data to the Powertrain Control Module (PCM)?

Technician A says that the Powertrain Control Module (PCM) or Transmission Control Module (TCM) varies shift timing and pressure based upon the transmission fluid temperature (TFT) sensor readings. Technician B says that TOT readings can typically be viewed using a scan tool. Who is correct?

To test a throttle position sensor (TPS), measure the voltage on the signal return wire with the vehicle in key on, engine off (KOEO) mode. The voltage should be close to 5V with the throttle closed and gradually drop towards 0V at wide open throttle.

Automatic transmissions began changing from hydraulically controlled to electronically controlled during the late 1970's and early 1980's.

Which of the following describes how shift solenoids are controlled by the PCM?

Technician A says that a faulty TPS can cause a transmission to have erratic shifting. Technician B says that a TPS operation should be verified with a DSO. Who is correct?

Which of the following vehicle speed sensor designs produces its own voltage?

Many four-speed automatic transmissions use ________ shift solenoids to control the transmission.

Technician A says that a CVI number of 190 indicates that the transmission is slipping. Technician B says that CVI numbers range from 0 to 255. Who is correct?

Technician A says that the MAF sensor measures the mass of the incoming air. Technician B says that a MAF is used because the more air entering the engine means the harder an engine is working. Who is correct?

In a _______ controlled transmission, the shift points are controlled by hydraulic and mechanical devices such as springs and valves.

Slippery conditions require a _______ that enhances traction and the stability of motion of the vehicle.

Technician A says the brake on/off switch is used to control the Torque Converter Clutch (TC disengagement). Technician B says on some newer vehicles, the brake switch is also used to put the transmission in neutral while idling at a stop light. Who is correct?

When measuring line pressure in an automatic transmission with a maximum available pressure of 200 psi, and the Electronic Pressure Control solenoid commanded value at 50%, which of the following measurements would you expect the actual line pressure to be?

A vehicle comes in with the check engine light on. The vehicle is scanned and has transmission ratio error codes for 1st, 2nd, 3rd, and 4th gears (i.e. all forward gears). Technician A says that the problem could be a faulty output shaft speed sensor. Technician B says that the problem could be a faulty transmission front pump. Who is correct?

Technician A says the Engine Coolant Temperature (ECT) sensor is not like the Transmission Fluid Temperature (TFT) sensor. Technician B says the Powertrain Control Module (PCM) or Transmission Control Module (TCM) uses the ECT to vary shift timing and pressure based on engine temperature. Who is correct?

Technician A says that the PCM monitors the speed of the input shaft and the crankshaft to slowly lock the converter clutch. Technician B says that the TCC is controlled only by the brake light switch. Who is correct?