Key-On/Key-Off Strategies - Alfa Romeo 159 Training Material

ELECTRICAL
SYSTEM
ECU programmed/not programmed
ECU OK/not OK
Wheel indication with spare wheel management
Tyre pressure: advanced information (axle imbalance, rapid or slow loss of pressure)
Advanced tyre state indications (axle imbalance, rapid or slow loss of pressure)
TPMS on/off
Run-flat tyre management (indication of remaining distance)
The four wheel pressure/temperature information (information on the spare wheel is optional) must be available on
the network within 10 sensors from key-on. After this start-up phase, the information above will be managed on a 15
second basis with regular/on-event messages.
The NQS acquires these signals and manages the respective indications.
The message is transmitted regularly via the A-Bus from the CPP every 15 seconds. A CPP anomaly signal is sent
and displayed by the NQS if the body computer does not receive a message for one minute.

9.5.9 Key-on/key-off strategies

If an anomaly is reported during key-on (ECU failure, low pressure), the information will be represented at the next
key-off/key-on cycle only if the anomaly occurs again. Specifically, in the case of run-flat tyres, the CPP ECU is
capable of correctly managing residual distance (run-flat management).
If loss of pressure from one or more tyres occurs during key-off, the respective message will appear on NQS (within
10 seconds) at the following key-on as shown in the finalised tyre pressure monitoring system ECU specifications.
Wiring diagram
Traccia Didattica Alfa 159-en-ridotta.doc
ALFA 159 TRAINING MATERIAL
280/319
Fiat Auto S.p.A.
After Sales Training
© 2004 Fiat Auto S.p.A. - Tutti i diritti sono riservati