47ho

4.7 litre High Output V8. Grand Cherokee WJ/WG, 2002 to 2004.

A diagnostic tool for this one car, built by an owner because the usual apps stop short of it.

Diagram: the diagnostic tool on the single-wire PCI bus, with sixteen control modules attachedToolvia the16-pin portEngineCD changerTransmissionClimatecontrolABSDriver doorBodycomputerPassengerdoorAirbagRain sensorInstrumentclusterMemory seatOverheadconsoleImmobiliserRadioAlarmPCI bus10.4 kbit/sDiagram: the diagnostic tool on the single-wire PCI bus, with sixteen control modules attachedToolvia the 16-pin portEngineCD changerTransmissionClimatecontrolABSDriver doorBody computerPassengerdoorAirbagRain sensorInstrumentclusterMemory seatOverheadconsoleImmobiliserRadioAlarm
The car's low-speed data network: Chrysler's PCI bus, SAE J1850 VPW, one wire at 10.4 kbit/s. Each of these sixteen modules answers the tool.
16 modules mapped
Every controller on the bus identified and talking, from the engine computer to the rain sensor.
Live data
Engine, transmission, ABS and body computer values, read while the car is running.
Drive logging
Whole trips recorded, so a fault can be studied after the drive instead of guessed at the roadside.

The full build log is on its way: how the network is laid out, what each module will tell you, and how the tool is coming along. The app itself stays private; the notes are for fellow owners.