FSI MAP sensor wiring

nod

Member
I've got a MAP sesnor error code on my FSI and have just been checking that the sensor is getting 5v power to it. there are 3 pins. Elsawin shows pin 3 should be 5v and pins 4 and 1 should be 'sender earth'. when i checked the voltage getting to the pins with ignition on i see 5.1v at pin 3 as expected, 0.1v at pin 1 as expected, and 5.6v at pin 4. Is this correct or could this be the problem? i'm just trying to rule out the wiring before stripping it down to change the sensor. many thanks
 
What's the error code that is being reported, perhaps this will give you an idea of the problem?
Can you get any readings from the sensor? - VCDS shows this detail in the measuring blocks.
 
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Pin 4 is the signal output from the sensor going to the ECU input. I wouldn't put anything to measuring a voltage here. If you want to verify the wiring, unplug the ECU and check that the wire on pin 4 doesn't connect to either ground or battery positive. It should not connect to anything once the ECU is disconnected. If it does then there is a short somewhere. You can also verify that the signal pin 4 goes to pin 84 on the ECU as a continuity test. If all of this is OK then your sensor is faulty.

regards

Andrew
 
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thanks for the advice. i disconnected ecu and checked pin 4 with multimeter, nothing. so went ahead and swapped out the MAP sensor. That seems to have solved one error code. cheers. Two more to go...
 
@ajsellors is it PIN 84 on all models? 1.4TDI 90? I have no continuity on any pins of the MAP to PIN 84 and an error code for open/short on that Sensor.

G71 & G72 below are the ECU Pins labelled at the top Along J248? Would this be 71 for Pin 4?

1662743489975.png
 
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@jonjo
Never assume the wiring is the same for all models IT IS NOT. Remember you have posted your question on an FSI thread and in the process confusing others. It would have been better on a new thread as you are asking about a tdi 90

The wiring diagram you have posted is the correct on for the ATL engined car. So yes pin 4 from the G71/G72 does connect to pin 71 of the ECU IN THIS CASE. You can also see that this wire passes through 2 connectors T17d and T17h.

The continuity test is still carried out the same way by testing the wiring between pin 4 and pin 71 on the LOOM with the plugs disconnected. If there is no continuity then check each connector in turn.
 
@jonjo
Never assume the wiring is the same for all models IT IS NOT. Remember you have posted your question on an FSI thread and in the process confusing others. It would have been better on a new thread as you are asking about a tdi 90

The wiring diagram you have posted is the correct on for the ATL engined car. So yes pin 4 from the G71/G72 does connect to pin 71 of the ECU IN THIS CASE. You can also see that this wire passes through 2 connectors T17d and T17h.

The continuity test is still carried out the same way by testing the wiring between pin 4 and pin 71 on the LOOM with the plugs disconnected. If there is no continuity then check each connector in turn.
Ace thanks for confirming @audifan I’ll get in it tomorrow. Still waiting for the correct female socket from Audi but checking all other options to be safe!
 
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