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B1730

Symptom: Engine malfunctioning.The trip computer indicates incorrect average fuel consumption.

B1730

Fuel consumption signal faulty

Fault symptom

Engine malfunctioning.

The trip computer indicates incorrect average fuel consumption.

Important

Diagnostic trouble code B1730 will also be generated if the throttle is suddenly opened wide from a nearly closed position.


Diagnostic procedure



1. If the engine malfunctions, start by checking whether any diagnostic trouble codes are present in the engine management system. If there are, deal with them.

If not, continue with point 2.

2. Connect an ISAT Scan Tool, start the engine and select "READ VALUES" followed by "FUEL CONSUMED".



3. If the fuel consumption signal is OK, the reading obtained should increase as long as the engine is running.

The fuel consumption display always begins at zero each time the engine is started.

4. If there is no fuel consumption signal, check the signal sent to the main instrument display panel by connecting a BOB to its 56-pin connector (the main instrument display panel should not be connected).


Connect the Scan Tool's test leads to pin 8 and battery positive, then select "MEASURE" followed by "PULSE".

Start the engine and check whether any pulses are present.

If pulses are generated, proceed to point 6.

5. If no pulses are present, there is probably an open circuit in the wiring connected to the main instrument display panel. Check and take appropriate action.

6. There could be an open circuit between the connector and the processor in the main instrument unit control module. Continue fault diagnosis as described on .