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Diagnostic Trouble Code (DTC) Information






Diagnostic trouble code (DTC) information

Condition





S70/C70/V70 (-00)/V70 XC
The cruise control stalk and its buttons are directly connected to the engine control module (ECM). The buttons are gauged with a pulsed signal from the control module, where the signal is high (approx. 12 V) for 0.004 seconds and low (approx. 0 V) for 0.016 seconds. This means a period time of 0.020 seconds (0.004 + 0.016 = 0.020). When one of the buttons is activated, the engine control module (ECM) receives the pulsed signal on the connection that corresponds to the activated button. If the engine control module (ECM) registers that one of the signals from the buttons is high (approx. 12 V) when the pulse should be low and this lasts for 0.6 seconds, diagnostic trouble code ECM-928C, No signal, is generated. Diagnostic trouble code ECM-928C, High signal, is stored if the engine control module (ECM) detects that the Cruise On and Resume buttons are active at the same time, which is infeasible due to the design of the cruise control stalk and buttons.
Diagnostic trouble code ECM-928C, Low signal, is stored if the engine control module (ECM) detects that the SET- and SET+ buttons are active at the same time, which is infeasible due to the design of the cruise control stalk and buttons.
For upgraded software, released during year 2006 or later, certain adjustments have been made. Another condition is that vehicle speed shall be higher than 25 km/h (15 mph) for above tests to be active, which is different from earlier software, where there is no condition for vehicle speed.
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: Design Design

Substitute value

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.

Possible source

- Damaged steering wheel module (SWM).
- This diagnostic trouble code is generated in combination with other trouble codes. Information on the possible root cause is described.

Fault symptom[s]
- General warning lamp lit
- ETS warning lamp lit.
- cruise control does not function at all.