Diagnostic trouble code (DTC) information ECM-917F

See Diagnostic trouble code (DTC) information ECM-917F

Condition

Fig 1: Identifying PWM Signals From Accelerator Pedal Position Sensor To ETM

Courtesy of VOLVO CARS OF NORTH AMERICA.

Engine control module (ECM) and Electronic throttle module (ETM) both receive information about the accelerator pedal's position directly from the accelerator pedal position sensor's pulse-width modulated sensor (PWM). Then both control modules send out the information on the CAN-net, so that other control modules can use the information. Electronic throttle module (ETM) compares the pulse-width modulated signal directly from the accelerator pedal position sensor with the pulse-width modulated signal coming from the Engine control module (ECM) via CAN. If these two signals differ for longer time than 0.4 seconds, then this information is sent to Engine control module (ECM) which then stores diagnostic trouble code ECM-917F, Faulty signal.

Electronic throttle module (ETM) also compares the desired throttle angle, which is sent from Engine control module (ECM) via CAN , with the pulse-width modulated signal coming directly from the accelerator pedal position sensor. If Electronic throttle module (ETM) registers that Engine control module (ECM) requests that an unreasonable throttle angle in relation to the existing accelerator pedal position for longer time than 0.4 seconds, then this information is sent to Engine control module (ECM) which then stores diagnostic trouble code ECM-917F, Faulty signal.

For upgraded software, released during year 2006 or later, the above detection times are increased from 0.4 to 0.9 seconds.

See Identifying upgraded software ECM/ETM

For more information about the electronic throttle system and related components such as the electronic throttle module, accelerator pedal position sensor, brake light switch, clutch pedal position sensor, and brake pedal position sensor:

See Design
See Function

Substitute Value

Closing of throttle during braking.

The accelerator pedal position is ignored when the brake pedal is depressed.

Cruise control off.

Cruise control off during entire operating cycle in which fault was detected. If the fault is no longer present, the function is available the next time the car is started.

For upgraded software, released in 2006 or later, adjustments have been made to substitute values. In driving cycles when the fault is active, closing of the throttle will take place at braking.

Possible Source

the power supply to the engine control module (ECM)
the power supply to the accelerator pedal (AP) position sensor
defective accelerator pedal (AP) position sensor
fault in the pulse width modulated signal cable between the engine control module (ECM) and the throttle unit

This diagnostic trouble code is generated in combination with other trouble codes. Information on the possible root cause is described.
See Information about combined diagnostic trouble codes (DTCs)

Fault symptom[s]

the accelerator pedal (AP) is ignored when braking
the cruise control cannot be activated
the ETS warning lamp lights (C70 and S/V70 -2000 only).