Cat 289D S/N TAW10455 I'm wondering what the supply voltage should be on the differential pressure sensor. Not signal voltage. The reading I am getting is 3.9 volts I feel like it should be 5v but I don't know. Question number two: Does anybody have my machine electrical schematics. On another post someone shared one but I am not sure if it's the correct one. The attached file below is the one I'm talking about. Thank you
Not it's not. It only covers TAW machines up to S/N 4108. Keep an eye on your message inbox. Normal voltage for that type of sensor on a Cat machine is 8v but this particular engine might be different because AFAIK it's made by Kubota. Let me check......... You mean this one, right.?
Yes that is correct.
I was doing some more testing last evening and pin number one with key on machine off is 5 volts. Signal is .7 or .8 volts. Just for kicks I also tested the boom position sensor. Supply voltage is 5 volts also.
Do you have a DMM that measures duty cycle.? Usually these sensors are PWM type and output a form of square wave signal rather than a voltage. Still waiting for confirmation of the engine sensor supply voltage. Remember that voltage is generated internally in a different ECM to the machine and they may not be the same. A quick look at the machine ECM shows that the sensor power supply for non-engine sensors is 8v. In fact some sensors such as the lift position (boom angle) sensor is actually supplied with battery voltage, unless the electrical schematic is drawn wrong. Was that the one illustrated below you were measuring.?
Yes that is the one. I don't see on the schematic where it shows what voltage it should be.
Read the table on the message I sent to you......... Failing that foillow the supply back to wherever it comes from.