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VeightTT
07-04-2017, 10:28 PM
Hi, I have had my HFS-4 (3.1) system installed (professional install) in my '13 Audi S6 for a few months now and I have never been able to get a smooth flow on the gauge, after extensive testing this week I discovered that the system is not reading any boost signal. I took it back to the installer to make sure all the wires are hooked up properly and it look like they are. My car is running 20psi the board is still configured at its default setting of 3.5bar. with the board configured to trigger off MPS should I still be registering at least some flow on the gauge? or is the 3.5bar to far out of range to pick up the signal?
if triggering off IDS with the system not reading any boost should it still behave as expected? Or is the lack of boost signal throwing everything off? I still have a few questions but I will leave it at this one for now.
The car is a 4.0 twin turbo with 2 1cc jets installed post intercooler one in each intake tract.

I appreciate any help
Cheers
Andrew

Richard L
08-04-2017, 06:20 AM
1. What is the engine code of your car.
2. Which wiring diagram did your professional installer use?
3. What is the serial number of the HFS4
4. What is the name of your installer?

VeightTT
08-04-2017, 07:18 AM
Hi Richard

1 CEUC
2 I believe it was for a C7 RS6 which he was told was the same ECU, wiring etc.
3 121750
4 Driver source (U.S)

The only other thing I can tell you is that the Map sensor (blue wire) is hooked up to ECU pin 47 per the wiring diagram.

Cheers
Andrew

Richard L
08-04-2017, 06:36 PM
This is correct pin 47 fore the G71 Map sensor.

Can you check the MAP sensor voltage on testing #17 at:

1. pre-crank
2. idling

VeightTT
08-04-2017, 11:20 PM
Testing at #17?
If that involves removing stuff in the engine bay to get to other stuff to test then unfortunately that is not something I am able to do, that will require booking the car in to have it tested and that will likely take some time. Also it would be helpful if you could tell me what I (they) should be looking for and what to change if not correct so it can be done in one trip to save time (and money).
Is there anything thing that would be helpful to you in the mean time? I can data log boost pressure, absolute, specified etc, etc. via VCDS and send you the logs.
Should the system be able to run of IDC correctly in the absence of boost signal?

Cheers
Andrew

Richard L
09-04-2017, 06:20 AM
The voltage is from the controller box. Should be in the glove compartment.

In order for me to help you, you really need to access the controller now and in the future. At the moment, I cannot help you any one of your question until I know what the settings are.

VeightTT
09-04-2017, 07:40 AM
Yes of course I can access the controller you just need to tell me where to put the multi meter to test for the voltage etc. the back of the board 3.5bar default?

Cheers
Andrew

Richard L
09-04-2017, 02:40 PM
There are thirty test points on the controller. Do you have a user manual you can get the infos from?

VeightTT
09-04-2017, 08:56 PM
yes I have a user manual

Richard L
10-04-2017, 05:54 PM
go to page 10.5

Pin 17 is the raw signal from the map sensor. (blue wire of the grey harness)

VeightTT
11-04-2017, 04:51 PM
Sorry for the late reply Richard I had to buy a new multi meter my old analog one was not sensitive enough to read the voltage.
so the readings I am getting are:-
pre crank .036
idle .042

Richard L
11-04-2017, 06:01 PM
OK, there is no boost signal as expected. Can you probe the little blue wire (grey harness) at the engine side and see if you can read and voltage signal there.

VeightTT
11-04-2017, 08:20 PM
I am unable to get to the wire that is plugged into the ECU but I can tell you when I was at the installers last week to have the wiring checked, there was power where the blue wire was tied in to the ECU (tie in point I believe), I don't know what the voltage was though.

Richard L
12-04-2017, 07:24 PM
As far as the controller is concern the blue wire is not wired to the MAP sensor. If you cannot check the blue wire connection then this diagnostic work is drawn to a close.

Try probing the gold tap on the RJ45 plug, you should be able to locate the tab where the blue wire is.

Who installed the system?

VeightTT
12-04-2017, 09:36 PM
I took the car over to the installers today and have to drop it off on Monday and they will check the wiring again and make sure it is connected to the map sensor etc. I will let you know as soon as I know.

cheers
Andrew

VeightTT
13-04-2017, 03:58 AM
one more question for your Richard if you don't mind.
Before I hopefully get everything working properly next week the only way I can get the system to run right at the moment is in single stage mode. Is the threshold trimmer the only thing that effects single stage mode? so as soon as the threshold trigger is hit it just sprays at 100%
I assume thats the case but just wanted to make sure.

Cheers
Andrew

Richard L
14-04-2017, 06:11 PM
Have you tried to run 100% IDC only?

- THRES: 10am
- P/I-R: 4pm
- GAIN: 12 pm

Jumper link:
- TRIP: IDC
-MODE: PWM

Let me know

VeightTT
15-04-2017, 08:45 PM
I am running of 100% IDC (TRIP: IDC) at the moment but set to SSG. I have tried virtually every setting there is to try.
I will give the settings you suggest a try and let you know how it goes.

Cheers
Andrew

Richard L
16-04-2017, 05:58 AM
I really think there is a wiring issue, I have never encountered these issues. Unless of course the controller is damaged.

Can you take a super -hi res picture of your controller, both top and bottom and post it to richard at aquamist.co,uk, I like to examining it closely.


Meanwhile can you take a few more readings on the test points for me?

VeightTT
16-04-2017, 06:58 AM
Sure I will take a picture of the board. What test points do you want me to test?

Richard L
16-04-2017, 07:18 AM
test points:

TP #5 ........... Steady 12V, system start signal.
TP #11 ......... 9V internal reference
TP #15 ........... 5V internal reference
TP #16 .......... IDC signal. voltage should increase with stabbing of pedal.
TP #20 .......... Trigger setting

VeightTT
16-04-2017, 10:57 PM
TP 5 - 14.15
TP 11 - 8.94
TP 15 - 4.95
TP 16 - 0.05 - 0.32 (throttle blip)
TP 20 - 0.59

Richard L
17-04-2017, 07:39 AM
The results are good except for the IDC signal, It is a bit weak.
Got the nice pics from you yesterday, all looks good,

Next test:

Link FDC (hi-jack gauge to display F-IDC) and let me know how many bars is displayed on the gauge at WOT.

Richard L
17-04-2017, 09:47 AM
I have found a pin out error on the previous drawing (v1), here is the corrected version (v2): Many apologises


http://www.aquamist.co.uk/HFS4/wiring/Audi-RS6/H4v3,1_CEUC.gif

VeightTT
18-04-2017, 02:49 PM
Hi Richard
I had my car at the installers today had it re-wired and tested all was good at the engine side but there is still no boost signal everything else is working as before. I have tried all different settings trip - mps, trip, p/I-r, threshold turned all the way down gain at max etc, etc. idle voltage 0.40

Cheers
Andrew

Richard L
19-04-2017, 08:42 PM
Did you see the new drawing above, the map sensor is on the right side of the ECU.

I like you to take a picture of the MAP sensor wiring on the ECU. I want to see this rather based on your words.

VeightTT
09-06-2017, 05:33 PM
Hi Richard
I finally managed to pull the ECU and get some pictures for you all the wiring and connections are good I am getting good voltage at the tie in to the map sensor all the way to the connection to the grey harness plug but its not making it to the board. I don't seems to be able to upload photos so I will e-mail them to you

Richard L
10-06-2017, 08:12 AM
email to richard at aquamist.co.uk

VeightTT
10-06-2017, 08:15 AM
I e-mailed the photos to you after I posted the last msg

Richard L
10-06-2017, 08:19 AM
found them.Are you Andrew?

VeightTT
10-06-2017, 08:20 AM
yes Andrew

Richard L
10-06-2017, 08:22 AM
I saw the voltage of 0.771v at the ECU. it is quite low for the MAP sensor. It should be around 1.5v at pre-crank. Also check the continuity of the blue wire of the grey harness because the the same voltage was not appearing the the RJ connector.

VeightTT
10-06-2017, 08:37 AM
yes the continuity has been checked the voltage is not making it from one end to the other. how else am I supposed to check it?

Richard L
10-06-2017, 08:56 AM
I suppose you can use the resistance option on the Fluke to probe the the two ends on the the blue wire. It should be near 0 ohms. One end on the gold figure of the RJ. May need to sharpen your probe.