Day 35 sheet

‘95 Freightliner Truck with a CAT 3406E

 

DTC – 108 (FMI 3) – this code is for Barometric Pressure Sensor with a voltage above normal or shorted high, or open circuit.

The Modis told me that the Barometric pressure sensor was reading 14.5psi. I found the sensor on the engine and found that is was disconnected, so I plugged the sensor back in. The read I got then was 15psi

Then I hooked up the CMP sensor to the Modis to see the signal the sensor was making.

If you look at the pattern there are three spots the are different than the rest. So as the camshaft goes around the ECM can tell were number one piston is coming to and at TDC on the compression stroke.