Jump to content
SAU Community

Apexi RSM: Installation Question

benm

By benm,
in General Automotive Discussion

 Share

Recommended Posts

benm Grand Master

benm

Posted
Posted

Just curious... for the people with the new style RSM (blue screen) does the actual RSM need to be plugged in for the car to work (like can the car/ecu still work 100% with the RSM plugged in).

The RSM has a permanently connected cable which has a plug at the end of a 2ft cable. Their is then another plug with another 2ft of cable which is what actually connects to the ECU wires. If I was to connect it all up but then disconnect the RSM would everything still work or would it leave some of the loops open?

Are you confused? I'm not far off it... :)

Link to comment
https://www.sau.com.au/forums/topic/36443-apexi-rsm-installation-question/
Share on other sites
strutto Grand Master

strutto

Posted
Posted

I think you may find that the speed signal doesn't get "passed" on to the ECU...

In my experience, the speed sender on the gearbox passes the signal to the dash cluster... This drives the speedo... The signal is then passed on to the ECU...

The RSM intercepts the signal between the dash and the ECU...

There are two methods of wiring the RSM IIRC... One where the signal is intercepted and the speed cut can be changed... And one where the signal is tapped and the speed cut remains factory...

I'm unsure what happens when the speed signal doesn't get passed to the ECU? Perhaps those who have cut wire 53 will be able to elaborate on the effects of having no speed signal to the ECU...

All the other wires should be fine...

Birnie Veteran

Birnie

Posted
Posted

i agree, the only problem would be the speed signal as the rest only tap in to what the ECU sees whethere the RSM is there or not. ie, the speed wire is acually cut and runs thru the RSP and then to the ECU.

I can't see this being a problem though if the ECU doen't get the speed signal.

Because it must be altering it or removing it altogether for the car to work over 180km/h.

If you are still worried about it, wire it the alternate way which only taps into the wire without doing the speed cut. Then it would DEFINATELY work plugeed in or not.

I've got one so i guess i should unplug it and give it ago but i'm stuck at work now for 12 hrs :)

benm Grand Master

benm

Posted
  • Author
Posted

Edited again....

What im trying to do is have it so that i can disconnect the RSM 'while' im at work (to try and help prevent theft etc). So when im driving i'll -always- have the RSM connected. I was just thinking that by connecting <-> disconnecting the RSM it might muck up the ECU or speedo or something while the car is sitting there off.

Birnie Veteran

Birnie

Posted
Posted

Should be no problem at all to disconnect when nt running I'd say.

Won't affect anything.

But anyway...what i do is a couple of matching velcro sticky strips.

One on the RSM and one on the dash in front of the standard speed dial.

Just enought room to see kms,boost and fuel...perfect!

The everytime i park, just 'rip' it off and place it under the dash where the pdeals are.

Sort of a reverse type shelf there and balances there fine.

benm Grand Master

benm

Posted
  • Author
Posted

Well I plugged it all in and it switches on etc and is working but the only problem is the wire that im sposed to splice for the 'revs' does not exist on my harness, its empty???

Has anyone here installed 1 on an RB25DET recently?

Birnie Veteran

Birnie

Posted
Posted

Yep, did mine myself (and my brother) and if it's blank, your not reading it right.

We read everything quite a few times and made notes on colors positions of wires etc....

Did it all once and switched it on...

First thing we tried was Revs and all worked fine.

Maybe you're reading the wrong ECU diagram but it's definatley correct

Or maybe you've got it upside down but i doubt that as you've got the power working..

Good luck :P

benm Grand Master

benm

Posted
  • Author
Posted

Well the English (USA) is a different diagram number but their is only 1 - 16P-20P-20P harness in the entire Nissan section and its for RB25DE/RB25DET. In the Jap book it came with its a diff diagram numb but the same picture.

I'll have a look at it again this afternoon (in the daylight :P )

benm Grand Master

benm

Posted
  • Author
Posted

Can anyone tell me what colour their 'speed' wire is on the ECU harness? I have no issues getting power to the RSM but cannot for the life of me get a speed signal.

I have a '95 R33 GTS-t Series 1

benm Grand Master

benm

Posted
  • Author
Posted

Ok still trying to figure out this stupid thing.

Attached is a pic showing that I do not have a Rev output wire like shown in every single manual I've read. Are their any other wires nearby that I can connect the Rev wire too?

ecu-harness.jpg

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
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • CRSKmD
      R32 Sedan - Grip and Drift (have my cake and eat it too build)

      By CRSKmD · Posted

      Yeah one of the first things I out in when I started having catch can filling up issues. Still prefer to empty 1-2 times a track day rather than every session
    • Lithium
      Compressor flow comparison table

      By Lithium · Posted

      You'll find this link is probably more useful  Performance Turbochargers - Garrett - G GT GTX GTW Series Turbo TBG G35 1150 map may not even get added to my list depending on how it looks, the G35 1050 already is a mixed bag for making the numbers you would expect from the compressor map due to mismatch - I don't know how another 10lb/min of compressor flow is going to make that any better.   I've left out others for similar reasons as it's already getting quite big.   In terms of Precision, provide me with legit compressor maps for them and I'll do my thing   I'll add some more of the newer Xona Rotor options are they're pretty boss, I'd take a 68mm Xona over a G35 "1150" any day of the week - or Precision for that matter.
    • Duncan
      R32 Sedan - Grip and Drift (have my cake and eat it too build)

      By Duncan · Posted

      Ahh got it. Well maybe install a drain for the catch can somewhere down low and accessible like a wheel well too....
    • MBS206
      Help Understand GTT Boost Setup

      By MBS206 · Posted

      Before you blow your car up, have you checked you've made all the correct modifications to the wiring if you're still using the RB20DE loom?   Some things to look at: The pin used for the map sensor on the RB25DET, is the same pin used on the RB20DE for the Ring Gear Crankshaft Position Sensor, no idea what you've got it plugged into now. The turbo pressure control valve solenoid you're talking about on the RB25DET, the same pin is used for the Variable Air Intake Control Valve on the RB20DE.   The factory manual has the wiring pinouts in it for you to check everything. It also has the diagnostics process to read codes out. In addition, there's a great table that shows what sensors and what actuators not functioning will relate to which signals. And Nissan confirm the as everyone else has from experience, the Solenoid being disconnected won't cause a fuel cut. However, the turbo pressure sensor being missing / wrong, WILL cause a fuel cut. https://www.nicoclub.com/service-manual?fsm=Skyline%2FR34-Workshop-Manual-English.pdf
    • Butters
      Compressor flow comparison table

      By Butters · Posted

      I've been hunting info on the G Series II - this is best I have found so far(Link below). Still waiting on the G35-1150 comp map, kind of very keen   So how do we go about getting precision on that little table of yours ?   https://turbosbytm.com/sites/default/files/product/technical-info/Garrett-G-Series-II-Product_Flyer 25 30 35_1.pdf  
×
×
  • Create New...