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No P-Bus System Can Be Contacted



No P-bus system can be contacted

Fault symptom
Diagnostic tool indicates "No P-bus system can be contacted".

Diagnostic help
Communication with CIM is necessary for Tech 2 to be able to communicate with all systems.

The Diagnostic instrument main menu "All systems/Read configuration" shows a list of those systems with which the vehicle in question was equipped before the fault was detected.

The current status of each system is shown to the right.

"OK" if control module communicates correctly.

"MISSING" if control module is not on the bus.

"ADDED" if the control module has not yet been added.

"NOT EQUIPPED" indicates that the control module is not fitted to the vehicle.

NOTE: applies before reset of bus configuration.

The voltage between bus+/bus- and ground should be 2.4 - 2.6 V.

Functions in the diagnostic tool related to the fault
^ Read / Reset Bus Configuration
^ Read / Clear Bus Off Counter
^ Response Test

Checking the wiring harness

IMPORTANT: Move the wiring harness at several spots and in several directions to reveal intermittent breaks and short-circuits. Check switches, connectors and crimp connections for oxidation, retracted pins and pin clamping force.