Diagnostic trouble code (DTC) information

Condition 

If Electronic throttle module (ETM) registers a deviation between the brake pedal's position via the brake light switch signal and the brake pedal's position sent from Engine control module (ECM) via the CAN-network for 0.3 seconds, this information is sent to Engine control module (ECM) which then stores the diagnostic trouble code ECM-91DF, Faulty position.

For upgraded software, released during 2006 or later, the above detection time is increased from 0.3 to 5 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:DesignFunction

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, no replacement values will be generated.

See Identifying upgraded software ECM/ETM

Possible Source 

• the power supply to the engine control module (ECM)
• open-circuit, short-circuit to supply voltage or short-circuit to ground in the signal cable for the stop lamp switch between the engine control module (ECM) and throttle unit.

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).