12 replies to this topic

[chefy83]

Just brought a Gen2 wags with a B4 motor in it. Has a few issues one of which is the speedo, it was never wired in and a GPS digital speedo was being used.
Any idea how different the wiring is between the gen 2 and 3 speedos? Ill have to dig behind the dash and see if i can find anything.

Any help would be appreciated!

[Barbbachello]

Gen 2 uses a 2 wire speed sensor. The power comes from the instrument cluster to the sensor which sends back a signal to the cluster which is then sent to the ECU.

The gen 3 uses a 3 wire speed sensor. Power and ground come from the loom and the signal goes to the cluster/ecu separately. Which sensor you should use will depend on how the engine and ECU is wired in. Both sensors are swappable with the right wiring however 

[Jimbo]

NFI how they wired it Nick, it uses the Gen2 nugget cluster. I thought it would have been a speedo cable not wired.

[Barbbachello]

NFI how they wired it Nick, it uses the Gen2 nugget cluster. I thought it would have been a speedo cable not wired.

Speedo cable stopped with gen 2 and v4 wrx. All gen 2s are electronic. What ECU is it using? Also is it a gen 3 TT or gen 2 TT? If the cars not complaining about the lack of speedo which it shouldnt, idk why it even asks for it. Just rewire it yourself is probably the easiest option

[Jimbo]

Its had a 2001 AU B4 cut put into a early Gen2 n/a wagon.

[Barbbachello]

Ok well its probably got the B4 speedo drive in it then. Ill dig up some diagrams tonight

[Jimbo]

Yeah I thought so, I don't they ever got to wiring it in properly. Me mate (chefy) bought it last week and there's a few things which need doing. 

The aircon hasn't been wired in either apparently.

Tell ya what, the B4 donk in a lighter Gen2 goes forking hard!

[Adam]

If you need any bits cheap let me know. I'm parting out a gen 2 wagon

[chefy83]

Yeah i had a look around. My understanding is the wiring goes from speedo drive to tcu then to the ecu then its supposed to goto the speedo... So i guess i just have pull the dash and hunt the wiring. Not even sure where abouts the gen 2 wiring for the dash has been spliced in.

[Barbbachello]

Yeah i had a look around. My understanding is the wiring goes from speedo drive to tcu then to the ecu then its supposed to goto the speedo... So i guess i just have pull the dash and hunt the wiring. Not even sure where abouts the gen 2 wiring for the dash has been spliced in.

Is it auto or manual? If its manual there is no TCU. 
Heres the pinout of the cluster which includes the VSS
https://www.dropbox....pinout.PNG?dl=0

[duncanm]

Auto - there are two speed sensors in the box which go to the TCU.

 

Manual - speed sensor goes straight to the meter and ECM

Auto - TCU sends equivalent speed signal to the meter and ECM

 

Manual speed sensor is a simple three wire - power (3), GND (2), signal (1).

 

 

 speedo.png   45.86KB   1 downloads

[chefy83]

Ok thanks for that ill probably pull it all apart tomorrow and see if i can find it...

[chefy83]

The gen2 is a three wire plug on the back of the cluster. Im guessing its pos, neg, and signal again but which is which and where does it get the pos and neg from....