Jump to content
Please check your junk folder for registration emails ×
  • Current Donation Goals

    • Raised $0.00

ECU power steering switch purpose?


Recommended Posts

I am running a bit low on inputs to my ecu and want to re-purpose the power steering switch input... I am assuming it's just to let the ecu increase the idle speed

slightly when the steering wheel is moved... and probably don't need it with my already very high idle. But does anyone know if it servers a more important function

than that and should be left connected? WRX GC8 btw.

Link to comment
Share on other sites

  • Admin

My understanding is the same as yours, that it's an idle-up to prevent the engine stalling under PS load, say if you're turning the wheels with the car stationary (which results in a lot of PS load as well).


Try disconnecting it at the pump end and see what happens?

Link to comment
Share on other sites

How about the ignition switch input? Seems a bit weird to have an input telling the ecu that the ignition switch is on, when it would not even have power otherwise.


edit...  its not an input.

Edited by Loren
Link to comment
Share on other sites

I was confused and thought that one of the inputs was the ignition switch... but it's not.

Used all the inputs now... if I want to add more sensors I will have to figure out the CAN comms

stuff which looks scary. Though O2 sensors have their own inputs, but have to $1000 for upgrade code

to use those... gps and accelerometers will need CAN I think.

Edited by Loren
Link to comment
Share on other sites

Can isn’t that scary from the little I’ve used it. 


Each thing has a unique address and broadcasts that followed by its data to everything else on the bus. 


Somethings like the main ecu are set to capture a set of addresses and read the data.


few wires and a few resistors. Mostly it’s friendly and companies make expensive connectors that make it plug and play. 


Link to comment
Share on other sites

  • Auckland Member

You might already know but CANs a great design because the noise on each line induces an inverted signal in the other line effectively cancelling all noise. Inbetween the two ends you can splice on whatever is necessary. 

As long as you have the terminating resister between the lines at the end of each bus, 120ohms from memory, and match all the signal rates, endianness, and ids it should all go smoothly...

What ecu are you running? Sorry if it's obvious on mobile atm and haven't read much. With a good ecu you shouldnt even have to worry about any of the low level stuff anyway, just type in the correct frame ID for the sensor on the line, set the correct transmission rate and go. 


A CAN sniffer off ebay/aliexpress wouldn't go amiss for troubleshooting at hardware level. You can make sure you're sending out the right frames this way.

I've done a bit of work with can buses on arduinos, stm boards, and motec ecus so can field some basic questions if you have any particular ones but by no means an expert. 

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recent Status Updates

    • MrSg9Sti04

      Afternoon team,
      im new to the group first time posting. Im hoping some body can help me get my launch control all dialled in on my link g4x. Ive had the computer and car all tuned from chris at prestige awesome knowlegable guy super happy with the results but now im wanting to get my launch/anti lag all dialled in. Ive been reading multiple different forums etc all with different conflicking information which has made me nervious with what do i listen to this or that if you get what i mean. Now ive started to make myself familiar with my PClink software etc the past few weeks and im eager to learn how to do minor setups or tweaks etc so im not relieing on my tuner so much and obviously saving myself abit hurt in the back pocket. 
      Now back to the question at hand.... Im wondering if theres and one who could please share there knowledge and wisdom with setting all my values, timing, fuel etc when i have launch control armed and engaged, or even a launch tune file they can possibly send me to load onto my tune. Ive figured out the setup of my digital inputs turning launch control on etc and its obvisously on its pre set factory settings. It engages but doesnt sound the greatest or as angry as it should i feel. Hence reaching out to you good buggers. 
      Cheers in advance for any info and help yous maybe able to give me.
      Cheers Shaun
      · 0 replies
    • Joker  »  gotasuby

      updated your DP's too : hope that's ok!
      · 0 replies
    • Joker  »  SAS

      Updated your DP's to reflect your business page  
      · 0 replies
    • Joker  »  Nachoooo

      Updated your Avatar : couldnt help myself  cheers!
      · 0 replies
  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Forum Statistics

    Total Topics
    Total Posts

  • Create New...