The wave form below is taken from a 206 DW8 diesel engine, running at idle.
It shows the crankshaft sensor, which in this case represents 'TDC' only and the Injector 'needle lift' sensor on cylinder No.1
The wave forms below are taken from a Citroen C8 HDI, (same as 807 DW10 RHT engine), accelerator pedal sensor. The reported fault code was 'P0221', accelerator pedal sensor coherence fault and was intermittent. The signal, at first glance, looks perfectly ok. On closer inspection you may note that the signal voltages are not correct, even although the relationship between the two signals is correct, the amplitude is incorrect.
The following wave forms are taken from the same vehicle as above, only with a new accelerator pedal sensor fitted. Now you can see the comparison and relationship of the sensor signal voltages. ('A' is double 'B' and the voltage amplitude is correct).
The wave forms below are taken from a 306 DW10td HDI accelerator pedal sensor. Coherence fault recorded and the operation was knotchy.
Engine speed sensor signal, Hall effect. DV4td engine.
Injector signal taken from EDC16 system. Good signal. DV4td engine.
The image below is also a 'Trendplot' recording. It is a DW10 HDI engine temperature sensor failing rapidly. This fault was not detected by the ECU.
Last Reviewed: 12 April 2008Copyright © 2004...2009 Mark Stammers mark@peugeotmt.co.uk