Author Topic: Code 17956 - N75 issues?  (Read 2061 times)

Offline Bfstrachan

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Code 17956 - N75 issues?
« on: 10 October 2014, 18:16 »
Looking for some insight please. My 1.8t AUM has been pretty poor on boost these past couple of weeks. I ran the vagcom and it came up with the "17956" code - N75. I have replaced with a new valve and the problems are no different. If the code is pointing to the N75 valve and I have replaced that, what can the cause be for throwing up the same code? The boosing issues are pretty constant, but there are spells when the response is good and the car seems to behave.
Most times under acceleration the boost is there to start, but very quickly dies abruptly. I am looking into doing a boost pressure test, but need some pointers to make sure I am going down the right path.
Any thoughts?
« Last Edit: 11 October 2014, 11:52 by Bfstrachan »

Offline Wazzzer

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Re: Code 17956 - N75 issues?
« Reply #1 on: 10 October 2014, 18:48 »
17596

Linear 02 Sensor / Compensation Resistor, Short to ground

I'd look at your lambda sensor...


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Offline Bfstrachan

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Re: Code 17956 - N75 issues?
« Reply #2 on: 10 October 2014, 22:53 »
Appologies, I have got the code numbers mixed up! The code is 17956 and not 17596. Thanks for the shout, but my mistake on the code.

Offline Gti_Jamo

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Re: Code 17956 - N75 issues?
« Reply #3 on: 11 October 2014, 14:29 »
The code is an electrical 'open circuit' fault code so could be wiring related also. I'd check the loom that goes to the n75 for age related damage. Your likely hitting limp mode with that fault hence the low boost. An actual boost leak is likely to trigger other fault codes.


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Offline Bfstrachan

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Re: Code 17956 - N75 issues?
« Reply #4 on: 13 October 2014, 20:47 »
Thanks for that. I am looking into multimeter guides to learn how to test the wiring to the N75. If anyone can point me in the direction of how to test the valve and the wiring, I would appreciate it! The other code that was was thrown up was the 17704 relating to the temp sensor or thermostat. I have replaced both of these in the last 6 months, so was surprised at that one. Don't suppose the two codes could be relating to the same issue?

Offline Bfstrachan

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Re: Code 17956 - N75 issues?
« Reply #5 on: 15 October 2014, 15:11 »
Help needed. Can anyone tell me where the N75 electrical feed ends up, is it into the ECU? Is that the end I need to check for the open circuit? Trying to get to the bottom of the 17956 code. Is there a way to test the 2 pin connector on the N75 valve for current?
Thanks.