Evening everyone,

I'm probably in the wrong section but I'm not sure where to post..

 

I have a 2010 superb cbbb 2.0tdi 170ps

 

I have constant limp and glow plug light flashing. 

 2 faults- p0238 map signal too high

                P0113 IAT signal too high..

 

I cant seem to find a wiring diagram that gives the voltages  to test with ignition on.

 

I have checked for continuity from the ecu and all 4 wires are good, have been replaced from near the fusebox, to the sensor.. theres no continuity across the 4 wires either, from the plug to the

 

Also my atmosphere sensor keeps toasting every few months..

 

Is there anything else on this circuit?

Or is my ecu going in the bin.

Thanks 

Thanks to whoever for moving to the right section,

 

Forgot to mention, I'm on the 3rd map sensor, 051c 3 bar standard map, 

And voltages with key on eng off, 

1 is ground 

2 is 2.45v

3 is 5.00v

4 is 1.60v.

Thanks 

I have never seen a wiring diagram that shows voltages for each circuit.
The main software ODIS would have a possible test plan that might ask the tester to check voltages for XYZ, but it's unlikely you have this as it's dealer/independant garage software.

 

The fact you mention that atmosphere sensor keeps toasting every few months suggests a wiring issue could be frying it, or as you fear a bad ECU/control module could be reading weird things.

(History of the car is very important in painting the overall picture)

Do you have the wiring diagrams for the car yourself to trace all the connections?

3 hours ago, varooom said:

I have never seen a wiring diagram that shows voltages for each circuit.
The main software ODIS would have a possible test plan that might ask the tester to check voltages for XYZ, but it's unlikely you have this as it's dealer/independant garage software.

 

The fact you mention that atmosphere sensor keeps toasting every few months suggests a wiring issue could be frying it, or as you fear a bad ECU/control module could be reading weird things.

(History of the car is very important in painting the overall picture)

Do you have the wiring diagrams for the car yourself to trace all the connections?

Hi, 

I dont have any wiring diagrams for this car but the 4 wires from the map sensor go direct to the ecu..

And the intermediate connector is bypassed directly to the map sensor..

 

I only have vcds and Delphi Autocom which dont test the voltage.. 

 

Literally lost now apart from changing ecu.. 

 

 

4 hours ago, Davieduck said:

Thanks to whoever for moving to the right section,

 

Forgot to mention, I'm on the 3rd map sensor, 051c 3 bar standard map, 

And voltages with key on eng off, 

1 is ground 

2 is 2.45v

3 is 5.00v

4 is 1.60v.

Thanks 

I have had a little look at the wiring diagrams.
1. Ground
3. 5V

2 & 4 will be some Voltage, but cannot say as ODIS test plan would reveal a value/range if written.

 

 

EDIT: Just looking on Google, there is a few entries that link back to this very forum!

https://www.briskoda.net/forums/topic/461600-skoda-superb-trouble-code-p0113-p0238/

 

Now don't quote me on this, but on a Passat I had around that time with 170CR engine, there was a recall for the DPF Sensor that was being naughty.
Just because a fault code appears in G31 Sensor, does not always equal a fault with that part, it can be caused by a cascade fault further up the chain.
Not saying this is your cause, but doing some reading around this has been reported from another post on here.

Faulty wiring, and I think there is mention of a TPI for this type of issue also has been posted about.


Trying to fix some faults at home will be nearly impossible with the tools at your disposal, so could be a trip to dealers.

Are u sure that is the right diagram as the ecu pins are different numbers to what I have continuity with

Are u sure that is the right diagram as the ecu pins are different numbers to what I have continuity with

7 minutes ago, Davieduck said:

Are u sure that is the right diagram as the ecu pins are different numbers to what I have continuity with

I cannot be 100% certain as I had to guess some of the car parameters.

So I've been testing again with my multimeter, the two signal wires are 4.7volt and 5.3 volt from ecu with the wires cut at ecu connector so the power is definately coming out of the ecu, not a short in the wiring harness

 

Is this probably a short inside the ecu possible water damage.. or is it possible that the atmospheric pressure sensor by the cabin filter, is shorting somewhere and sending power back into the ecu and back out to the map sensor..

When I snipped the signal wire #2 and tested voltage on ecu side it is 4.7v and no 4  was 5.7.. but when testing with map plugged in, 2 was 2.46v and 4 was 1.6v

If you google G31 p0238 map signal too high, it will show several results from Briskoda.

Doing a lot of reading of the posts (some never come back to say what the actual fix was sadly - ask for help then leave)

• You can see that for one person there was a wiring fault with G42 temperature sensor built into the same part to measure pressure and temp in one unit.
• Another had a wire that had become rubbed under I think the airbox, and this caused it to keep coming back.
• Another was also down to the DPF sensor being faulty (recalled on VW Passat from my own personal experience)

I am not mechanic, but I would say this is more than likely to be a wiring loom issue with something rubbing through to earth or a live 12V feed into what should be a 5V signal max.

What diagnostic tool do you have at your disposal?  So can you get live values of temperature/MAP pressures.
You could also make your own account on erWin Skoda to grab lots of useful information, so wiring diagrams/repair manuals and any possible recall campaigns that are still outstanding.
 

I have vag com and Delphi Autocom, why would there be 4.7 volts coming out of the ecu to wire 2 and 4 on the map sensor..

1 minute ago, Davieduck said:

I have vag com and Delphi Autocom, why would there be 4.7 volts coming out of the ecu to wire 2 and 4 on the map sensor..

The ECU could be pumping out a CANbus signal, dunno to be sure.
Would need to know what someone else gets out of their ECU on those pins.

 

 

VCDS or VAG Com if you like to call it should have a log of the faults and the "live" parameters when it occured, so a nice snapshot in time.

 

 

So here's a nice full scan that can show a better picture.

Address 08: Auto HVAC (J255)       Labels:| 5G0-907-044.clb
   Part No SW: 5E0 907 044 T    HW: 5E0 907 044 T
   Component: Climatronic   H04 1002  
   Revision: 00001K07    
   Coding: 02110104000100011005000100101000
   Shop #: WSC 73430 031 00063
   ASAM Dataset: EV_ACClimaBHBVW37X 004131
   ROD: EV_ACClimaBHBVW37X_004_VW37.rod
   VCID: 366759E68973FD3F25-8062

 

   Fresh air blower control module (front):

 

   A/C pressure/coolant temperature sensor:

 

   Air quality sensor:

1 Fault Found:
329476 - Motor for Fresh Air / Recirculated Air Flap
          B108B 71 [008] - Actuator Stuck
          Intermittent - Confirmed - Tested Since Memory Clear
             Freeze Frame:
                    Fault Status: 00000001
                    Fault Priority: 2
                    Fault Frequency: 30
                    Reset counter: 141
                    Mileage: 230759 km
                    Date: 2022.03.07
                    Time: 17:11:12

                    Voltage terminal 30: 14.0 V
                    Outside temperature: 7.0 °C
                    Inside temperature: 23.8 °C
                    Actual value for fresh air/recirculation air flow flap: 0.0 %
                    Actual value for fresh air/recirculation air flow flap: 60
                    Fresh air/recirculating air/back pressure door specified value: 33

 

 

So if possible it might assist to post a full car scan (as never know if something else if related)

26 minutes ago, Davieduck said:

I have vag com and Delphi Autocom, why would there be 4.7 volts coming out of the ecu to wire 2 and 4 on the map sensor..

They are inputs not outputs, they do not put out 4.7 volts to the sensor as such, that is the open collector (I'm rusty but I think that was the term) voltage from a pull up resistor in the ECU, the sensor when it is working will pull the signal down proportionate to whatever is being measured, the ECU measures the reduced voltage to decide what the parameter value is, if the wire is snipped as you have done then it will measure the full open collector voltage and generate the confusing fault code "signal XYZ open or closed circuit"

VCDS/VagCom has a section called measuring blocks, and by scrolling through them you'll find the signals you are looking for and if it's the latest version if you hover the mouse pointer over the relevant block it with give an expected Hi & Lo figure

8 hours ago, J.R. said:

They are inputs not outputs, they do not put out 4.7 volts to the sensor as such, that is the open collector (I'm rusty but I think that was the term) voltage from a pull up resistor in the ECU, the sensor when it is working will pull the signal down proportionate to whatever is being measured, the ECU measures the reduced voltage to decide what the parameter value is, if the wire is snipped as you have done then it will measure the full open collector voltage and generate the confusing fault code "signal XYZ open or closed circuit"

The 4.7 is coming out of the ECU to an open circuit.. snipped wire.. I'd imagine it should be 0v coming out of the ecu as it is a signal input as you say should be getting 1 to 2.5 volts from map sensor to the ECU.

Pinout is as follows.

1 - 66

2 - 30

3 - 17

4 - 83

 

A black intermediate 4-way connector is shown, where the wires from pins 1 and 2 of the sensor connector both change colours (yellow to red/grey, and brown to brown/grey respectively); have you found and inspected that plug/socket connection, it's mounted on gearbox apparently.

 

I would expect the intake air temperature sensor (output on pin 2) to be the bottom half of a potential divider, so with sensor disconnected it would naturally float up to the voltage rail supplying the divider.

Not sure if the same applies to the output of the pressure sensor part on pin 4, but something similar may well apply, like a pull-up resistor as mentioned by @J.R.

The whole loom is insulation tape from the ecu to the engine..

I've stripped some of it back and its wet inside the tape. Am I as well off to strip the whole loom off and re tape with the proper furry tape lol.

 

Thanks too for the effort and replies lads, tiring pretty quick of this issue

3 minutes ago, Davieduck said:

I've stripped some of it back and its wet inside the tape

That doesn't sound helpful, I would suggest ripping all the tape off and just using cable ties every 100mm or so to hold the cabling together. Find and inspect that intermediate connection, it may be that water has run along wires and into the connector housings.

7 minutes ago, Breezy_Pete said:

Pinout is as follows.

1 - 66

2 - 30

3 - 17

4 - 83

 

A black intermediate 4-way connector is shown, where the wires from pins 1 and 2 of the sensor connector both change colours (yellow to red/grey, and brown to brown/grey respectively); have you found and inspected that plug/socket connection, it's mounted on gearbox apparently.

 

I would expect the intake air temperature sensor (output on pin 2) to be the bottom half of a potential divider, so with sensor disconnected it would naturally float up to the voltage rail supplying the divider.

Not sure if the same applies to the output of the pressure sensor part on pin 4, but something similar may well apply, like a pull-up resistor as mentioned by @J.R.

My intermediate connector was bypassed already and the 4 wires at the ecu were un-braided so clearly has the same issue before. 

 

I must have a different issue causing same codes if its supposed to creep up near 5 volts, I had no coffee before replying to @J.R.

 

I should mention,when I unplug my map sensor the electric water pump comes on making an awful noise until plugged in or key off

1 hour ago, Davieduck said:

I must have a different issue causing same codes if its supposed to creep up near 5 volts, I had no coffee before replying to @J.R.

 

No problem, it's a natural assumption and the concept of pull up or pull down resistors is not an easy one to grasp, basically if it were an open zero volt input (without a pull down resistor) waiting for a voltage to be applied by the sensor it would pick up all manner of stray radiated and induced voltages so pull up resistors are used with the sensor forming the second potential divider resistance.

Ok, I'll put the ecu and map sensor back as it was and try to trace atmospheric sensor and dpf sensors, it seems to have been a previous fault anyway as the wiring is replaced and soldered for map, otherwise i suppose I'll just have to try a different ecu. 

And open to any suggestions,

Thanks

Opening this topic again.
Can anyone show me the appropriate schematic page of the MAP sensor of a 2.0 TDI CR (CFFB)?
And know how to find the intermediate connector?

I have already replaced the MAP sensor. For what its worth: I have tested between pins 1 and 2 and there seems to be an NTC sensor in place.

The higher the temperature the lower the resistance.

That is why I think I have a intermitting bad contact between the sensor and the ECU at the intermediate connector. When I move the motor a little by use the gas pedal or shift gears I see the intake temperature on my ODB11 app jump to -40 degrees Celsius for a very short time, apparently -40 is the value belonging to the highest possible resistance.

When the -40 lasts long enough (half a second or so) the engine goes into limp mode. When I completely disconnect the MAP sensor the reading stays at a solid -40.

I have tested connectivity between the 94 pole connector at the ECU and the 4 pole of the MAP sensor with a multimeter and no matter how I wiggle and pull on the connecting wires/connectors at both ends it will not disconnect.

So: intermediate connector is the prime suspect, as breezy Pete says:"Somewhere on the gearbox". I could not see anything from below or above.
Should I remove the airfilter? (because it looks like the side of the gearbox. And is that a lot of work?)
Anything else to remove?

Thanks in advance,

Loek (that is how you spell "Luke "in Dutch)

Edited 4 June, 20251 yr by Loek

Hi Loek.

I can't really add anything that I haven't said above; circuit section is shown below, T4bl is described as "4-pin connector, in the holder on the gearbox (black)".

Thanks Breezy_Pete,

I will try this weekend to get to this intermediate connector by removing the Airfilter and maybe other parts.
From below it looks like the bundel of wires from the MAP sensor is going up in that direction.

What bothers me up front is that there seems a harnes bundling the MAP and a few wires attached to a 2 pole connector at the aircon pump.

But bundling seems unappropriate when T4 is only a 4 pole connector.

If I find this intermediate connector I will post a photograph here.

If not, my fall back quick and very dirty solution would be to draw a leadwire from the MAP to the ECU directly.
It is as good as impossible to follow the harness all the way up, so that will mean a creative route...

Regards,

Loek