IAT sensor, what does it do with regards to the fuelling? Also, speed sensor?

[Scott]

I feel that this is probably a stupid question so I've left it out of Technical in case Ian C has palpitations lol.

 

I've no idea who configured the Syvecs I have originally but they haven't half made a mess of it. So many wrong things chosen and selected in the inputs that it's thrown me way off when trying to configure it to my setup. For the record, it definitely wasn't Ryan lol.

 

Anyway, it's brought about a couple of queries that I would just like to have the information on.

 

How does the ECU use the IAT sensor? Does it adjust the fueling based on the charge temperature? I guess this is the case, after all we all know that colder air = more O2. Additionally, does the Syvecs do this automatically or is this something else that needs configured? The calibration for the sensor is all done, I just need to select the correct pinout. What I don't know, is if it will automatically start using the readings from the sensor once I have done this.

 

Next, as above, how does the ECU use the vehicle speed sensor? Does the ECU send the speed to the speedometer, or is it an independent signal? What does it take into account regarding the speed? What is it used for? The only thing I could think of would be traction control? I'm probably missing out something obvious though.

 

Thanks

[Wez]

It will have fuel corrections located at > Run-Mode fueling / corrections / Air Charge Temp Multiplier.

 

Also ignition corrections located at > Run-Mode ignition / corrections / Air Charge Temp Multiplier.

 

 

From Memory the clock cluster gets its speed inputs from the gearbox, when setting up traction control you can wire some convertors into the ABS sensors so that the syvecs sees the correct signal for wheel speed, on a MKIV normally two rear and one front since both fronts should be travelling the same speed or if you have enough inputs then both fronts too, I cant remember 100% its been a while

[Wez]

I have just checked an old calibration and I am showing four speed sensors wired in.

[Scott]

It will have fuel corrections located at > Run-Mode fueling / corrections / Air Charge Temp Multiplier.

 

Also ignition corrections located at > Run-Mode ignition / corrections / Air Charge Temp Multiplier.

 

 

From Memory the clock cluster gets its speed inputs from the gearbox, when setting up traction control you can wire some convertors into the ABS sensors so that the syvecs sees the correct signal for wheel speed, on a MKIV normally two rear and one front since both fronts should be travelling the same speed or if you have enough inputs then both fronts too, I cant remember 100% its been a while

 

Ahh that may just save my bacon Wez. I was wondering about the wheel speed inputs with regards to the ABS.

 

Hope you don't mind me picking your brain for a sec......

 

The ABS sensors are for the ABS, obviously, they connect to the ECU but I believe they also have their own ABS ecu? Would I be correct in assuming that if I used 3 sensors in the Syvecs for the wheel speed, this wouldn't effect how the ABS operated and performed? Just thinking of wet/snow braking.

 

I'm at the point now where I've ran out of inputs and I'm about to ditch my oil temperature sensor to make way for the traction control switch. If I could ditch one of the front wheel speed sensors, I could use that input for the oil temperature and then use the remaining input for the TC switch.

 

I emailed Ryan asking about it but I know he's a busy guy. It's often hard to get a response.

 

Thanks

[Scott]

I have just checked an old calibration and I am showing four speed sensors wired in.

 

I have 4 wired in at the moment, I also have another calibration that Ryan copied over that only uses 2 though. One front and one rear lol.

[Wez]

It shouldnt affect the ABS ECU or operation as you should simply be tapping into the signal.

 

Like I said its been a while since I played with it and I know the traction control has evolved since testing the first Syvecs on my MKIV, its quite possible that it only requires two, in its most basic operation you just need to know the speed difference from front to rear to work out if the rear is spinning, obviously knowing what each wheel is doing would allow for finer control.

 

If you have four wired in can you not just assign them in the calibration software under IO / inputs / wheel speed etc.

 

Again mine is old but my two fronts are configured as thermistor and the rears are 5v, this can be found under sensors / speed / input config.

 

Do you have any signal converters wired in like the ones Chris talks about here :-

 

http://www.mkivsupra.net/vbb/showthread.php?316889-Traction-Control-and-ABS-analogue-to-digital-converters

[Scott]

It shouldnt affect the ABS ECU or operation as you should simply be tapping into the signal.

 

Like I said its been a while since I played with it and I know the traction control has evolved since testing the first Syvecs on my MKIV, its quite possible that it only requires two, in its most basic operation you just need to know the speed difference from front to rear to work out if the rear is spinning, obviously knowing what each wheel is doing would allow for finer control.

 

If you have four wired in can you not just assign them in the calibration software under IO / inputs / wheel speed etc.

 

Again mine is old but my two fronts are configured as thermistor and the rears are 5v, this can be found under sensors / speed / input config.

 

Do you have any signal converters wired in like the ones Chris talks about here :-

 

http://www.mkivsupra.net/vbb/showthread.php?316889-Traction-Control-and-ABS-analogue-to-digital-converters

 

I have them assigned already. I believe they should be working as is, but the TC will need to be mapped.

 

Mine are the same as yours, 2 fronts are thermistor with the 2 rears being 5v and the RADAR (vehicle speed I guess) also 5v.

 

I don't have any converters in mine at all.

 

My setup at the moment is as follows:

 

AN1 - Cam Sensor

AN2 - Crank Sensor

AN3 - Wheel Speed RL

AN4 - Wheel Speed RR

AN5 - Vehicle Speed Sensor

AN6 - Air Con Switch

AN7 - Wheel Speed FL

AN8 - Wheel Speed FR

AN9 - TPS

AN10 - MAP Sensor

AN11 - Fuel Pressure

AN12 - Oil Pressure

AN13 - Coolant Temp

AN14 - Oil Temp

AN15 - Intake Air Sensor

AN16 - Boost Cal Switch

 

TC Switch is all that's missing

[Wez]

Here is mine, there are a few differences

 

AN1 - Cam Sensor

AN2 - Crank Sensor

AN3 - Wheel Speed RL

AN4 - Wheel Speed RR

AN5 - Lateral G

AN6 - Wheel Speed FR

AN7 - ALS Switch

AN8 - Wheel Speed FL

AN9 - TPS

AN10 - MAP Sensor

AN11 - Traction Control Switch

AN12 - Calibration Switch

AN13 - Coolant Temp

AN14 - Air Charge Temp

AN15 - Launch Control Switch

AN16 - Pit Limit

[Scott]

Here is mine, there are a few differences

 

AN1 - Cam Sensor

AN2 - Crank Sensor

AN3 - Wheel Speed RL

AN4 - Wheel Speed RR

AN5 - Lateral G

AN6 - Wheel Speed FR

AN7 - ALS Switch

AN8 - Wheel Speed FL

AN9 - TPS

AN10 - MAP Sensor

AN11 - Traction Control Switch

AN12 - Calibration Switch

AN13 - Coolant Temp

AN14 - Air Charge Temp

AN15 - Launch Control Switch

AN16 - Pit Limit

 

Do you know where the ECU is getting the vehicle speed from in your setup Wez? Just wondering if I could use the vehicle speed sensor AN5 for a switch. I'm guessing it's probably the wheel speed, but no idea how to configure that. Does your vehicle speed setup show "Radar" after the thermostor and 5v inputs for the wheel speeds?

 

Edit: Funnily enough, in "Vehicle speed select" mine says "AVG COND FRONT" rather than "RADAR". Maybe it was deliberately setup this way after all.

Edited March 9, 2015 by Scott (see edit history)

[Wez]

Mine is using AVG FRONT for vehicle speed

 

Driven wheel speed select on mine is AVG REAR

[Scott]

Hmm that's interesting then. With regards to your ALS switch. Do you think I could use the TC switch in the same way that you have with it? I ask as I notice from the guide that the cal switch input normally connects to an AR3 pin, whereas the vehicle speed one is an AU1 pin. Just wondering if it can be configured to work with the switch just the same.

[Scott]

Lee has just said that he sometimes only uses 2 wheel speed sensors (one front and one rear) in order to free up a couple of inputs. With that in mind, it looks like I may be sorted

[Wez]

Some info on pin usage from the Syvecs forum, it states they can be used to measure 0-5v input which is what you need for a traction calibration switch, are you planning to wire up a multi-position switch like a cal switch?

 

AB pins are Analogue Bipolar which means they can be used to measure voltages in the range 0-5V and -5V to +5V. Additionally they can detect speed signals with programmable trigger thresholds. There are four such pins :

 

AB1 is also known as AN01

AB2 is also known as AN02

AB3 is also known as AN03

AB4 is also known as AN04

 

AU pins are Analogue Unipolar which means they can be used to measure voltages in the range 0-5V and have an optional pull up resistor of 3k for temperature measurements. Additionally they can detect speed signals with fixed trigger thresholds of 1.25V and 3.75V. There are four such pins :

 

AU1 is also known as AN05

AU2 is also known as AN06

AU3 is also known as AN07

AU4 is also known as AN08

 

AV pins are Analogue Voltage which means they can be used to measure voltages in the range 0-5V but they cannot be used for speed measurements and they have no pull up resistors. There are four such pins :

 

AV1 is also known as AN09

AV2 is also known as AN10

AV3 is also known as AN11

AV4 is also known as AN12

 

AR pins are Analogue Resistance which means they can be used to measure temperatures and so feature a permanently enabled 3k pull up resistor but they cannot be used for speed measurements. There are four such pins :

 

AR1 is also known as AN13

AR2 is also known as AN14

AR3 is also known as AN15

AR4 is also known as AN16

 

NB: If the source impedance of a sensor is significantly lower than 3k then it can overpower the 3k pull up and AR inputs can be used as a 0-5V input.

[Wez]

Lee has just said that he sometimes only uses 2 wheel speed sensors (one front and one rear) in order to free up a couple of inputs. With that in mind, it looks like I may be sorted

 

Makes sense

 

EDIT: would also explain the cal you have with only two assigned

[Scott]

From what you have posted above Wez, would you say that I could wire in the TC switch (it's a cal switch like you thought) into AN08? I take it I can just cut the wire that's already in there and solder it on with the ground going to the same one as the current Cal switch?

 

Makes sense

 

EDIT: would also explain the cal you have with only two assigned

 

It explains it, definitely.... but it's not for my car. It was just the map Ryan used to set some default parameters so that he knew where he was starting from when sorting out my fuelling

 

 

Thanks for your help with this

[Wez]

Yes AU inputs can be used for a 0-5v CAL / TRC input.

 

Your vehicle speed select is currently AVG COND FRONT, I suspect this would need changing to the one remaining front speed sensor.

[Scott]

Yes AU inputs can be used for a 0-5v CAL / TRC input.

 

Your vehicle speed select is currently AVG COND FRONT, I suspect this would need changing to the one remaining front speed sensor.

 

Yip, I'll be changing that to the gearbox speed sensor. It's either that or i can leave it at AVG front which seems to be the recommendation from the setup guide that Ryan did and use the vehicle speed sensor for the switch.

 

Having re-listened to the traction control vid it appears I do indeed need the signal converters. Any idea where these things wire in?

[Scott]

Do you think this would work?

 

http://www.jbperf.com/dual_VR/v2_1.html

[Wez]

I would go with two front sensors and use the AVG COND FRONT for vehicle speed and use AN5 for the switch. Are you switches two or three wire?

 

I have old three wire ones which use GND, 5V REF and a white output signal wire for the ECU.

 

My install deff has some signal converters, they look like orange relays and are wired between the Syvecs and ABS sensor, Chris or Ryan would be best bet on this.

[Wez]

Do you think this would work?

 

http://www.jbperf.com/dual_VR/v2_1.html

 

Apparently yes but if you look here there is a comment from Ryan detailing the Siemens relay type unit and how to setup in sCal, this is what I have installed on mine

 

http://www.syvecs.co.uk/forum/viewtopic.php?f=6&t=553

[Scott]

I would go with two front sensors and use the AVG COND FRONT for vehicle speed and use AN5 for the switch. Are you switches two or three wire?

 

I have old three wire ones which use GND, 5V REF and a white output signal wire for the ECU.

 

My install deff has some signal converters, they look like orange relays and are wired between the Syvecs and ABS sensor, Chris or Ryan would be best bet on this.

 

Apparently yes but if you look here there is a comment from Ryan detailing the Siemens relay type unit and how to setup in sCal, this is what I have installed on mine

 

http://www.syvecs.co.uk/forum/viewtopic.php?f=6&t=553

 

Just before I went to bed I went on ebay and bought a couple of them, just on the off chance that I needed them. I'm going to go down the exact route that you suggested. The switches I have are 2 wire.

 

Out of curiosity, do you know where your converters are wired in? Is it on the fields harness or is it before that? Just wondering whether to butcher the harness on the syvecs or whether to further butcher the stock 6spd harness lol.

[Wez]

From memory mine are wired in behind the stereo near the ABS ecu.

[Scott]

From memory mine are wired in behind the stereo near the ABS ecu.

 

Makes sense. Keeps them clear of the footwell. Thanks again

[Chris Wilson]

I would use screened cable from the ABS sensor tap point to the analogue to digital converters, and from the A to D converters to the Syvecs. You might be interested in this thread I made a while back if you haven't already seen it.

 

http://www.mkivsupra.net/vbb/showthread.php?316889-Traction-Control-and-ABS-analogue-to-digital-converters&highlight=analogue+digital

[Wez]

I already linked your thread in post #6 of this thread as I recalled you knocking up some converters