[davchar]

Hi All,
I have built an MPGuino using the iDuino. The car that I am going to install the unit in is a 1991 Nissan Patrol (Safari) 4WD with a naturally aspirated 6 cylinder mechanically injected diesel. I have bench tested the VSS input on the MPGuino and the counter ticks up each time the input is pulsed 5v.

The manual that I have for the car states that if a multimeter is connected across the speed sensor in AC mode, a reading of 0.5v should be detected. Additionally there is an output from the speedometer which when I tested it with a multimeter seemed to pulse 0.05v DC as the vehicle moved.

The MPGuino did not detect any VSS pulses when connected to either the speed sensor or the speedometer output. It seems that these input are either not generating sufficient voltage or they are generating a signal type not expected by the gauge.

Does anyone have any suggestions on what I might need to do to get the MPGuino to interface with my car's speed sensor or speedometer output?

Thanks in advance,
David