PRE-RELEASE
Speed, bus from TC/ABS
| Speed, bus from TC/ABS |
The TC/ABS control module sends the bus message "Wheel speed, FR, XXX km/h” via the P-bus to ECM. This speed signal is used to:
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Determine the gear currently engaged. This ensures the engine receives the correct fuel quantity in different gears when the accelerator is released by measuring the road speed and engine speed.
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Give impulses to cruise control.
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| Diagnostics |
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If the speed value is implausible, DTC P0501 will be generated.
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If the speed signal is low, DTC P0502 will be generated.
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If the speed signal is high, DTC P0503 will be generated.
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System reaction to a fault
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The control module uses 0 km/h as a substitute value.
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Cruise control blocked.
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