ABS light in the dash illuminated and engine not starting!!

[Tappara]

What's happening!
I get err codes 12 and 52. 12 = FL wheel sensor and 52 = is Valve Relay "stays off".
Engine turns but doesn't start - like an Immobilizer fault, except that there is no err code for that.
Relay check showed it to be ok....
Fuse is ok.
Haven't checked the 12 as yet.
At no stage the Workshop Manual (WM) indicates anything about inability to start the engine if one has ABS fault - on the contrary, WM advises one to pull out the fuse if driving is required.
Baffled! :001_mad:

 

[Lasiorhinus]

Did you try pulling the fuse and starting?

Also, probably too obvious to mention, but you do have fuel in the tank dont you?

 

[Tappara]

Did you try pulling the fuse and starting?

Also, probably too obvious to mention, but you do have fuel in the tank dont you?

Did so and no diff. No ignition.

Heh, yee, plenty of gaso in the tank. And if it was fuel pump issue, I would get err code for it - I assume. Veeery strange stuff.

 

[hozza]

Check the relay in the center of the engine bay at the back. My wire insulation broke off mine and started shorting to each other and the frame. Also it they went on to give a 53 abs code which I think is the abs ecu busted. But at least it should start.

 

[Tappara]

Check the relay in the center of the engine bay at the back. My wire insulation broke off mine and started shorting to each other and the frame. Also it they went on to give a 53 abs code which I think is the abs ecu busted. But at least it should start.

The one near TB? I had a look and all seems visually ok. How ever, I'm disallowed to conduct any further car work over the weekend, says The Boss. Will continue on Mon. But, this is really strange stuff and I hope the solution is too simple to spot as yet. Cos - ABS failure should NOT prevent it from starting!

 

[Tappara]

Quick update:
Been slowly checking stuff and have so far noticed that gaso and injectors are dead, BUT ignition gets power ok. If this was an Immobilizer issue, the ign part of it would be dead too. One thought was that the aftermarket Mongoose Alarm system, which has immobilizing in it, could be faulty. It works fine on doors etc and it would also kill the ign.
So, not getting any closer rectifying this fault.

 

[hozza]

have you did you try looking at the valve relay?
No idea where it is but im sure one of the wiser heads here would know.

 

[Tappara]

Valve relay is near the ABS Valve/ECU box. That was checked and was ok.
I'm currently stuck with lack of wiring info and am waiting for the Haynes book to arrive mid next week - hopefully.
Might call the Alarm guy to see if he has any ideas, cos this sounds very much like ECU or Immobiliser issue - not ABS at all.
Just bit sick of it atm, really…. Grrrhhhh.

 

[qball]

Where about in NSW are you as i've got a spare ECU you could try to check if it is ECU related

 

[hozza]

Well I had an abs fault like i said and it caused my car to not start.

 

[Tappara]

Where about in NSW are you as i've got a spare ECU you could try to check if it is ECU related

Cool, tnx. I keep this in mind.
I'm in S/W Syd.

 

[Tappara]

Well I had an abs fault like i said and it caused my car to not start.

That was the earthing issue wasn't it? Or did you actually have to replace the ABS ECU?

 

[hozza]

That was the earthing issue wasn't it? Or did you actually have to replace the ABS ECU?

Not sure which two wires were shorted together but once i fixed them my car would then start.
But yes it fried my ABS ecu.

 

[Tappara]

Where about in NSW are you as i've got a spare ECU you could try to check if it is ECU related

Might take you on this offer, subject to further investigations coming week....
Could you send me a PM and tell me what car is the ECU from - we don't want massive Graft vs Host issues if it doesn't match my -02 VR4 TT. Also, where do you live?
Cheers.

 

[Tappara]

Any one willing to disconnect ABS and try starting the engine?
Would be interesting to see if ABS ECU issue really would disable starting in TT VR4.

Procedure:
Turn off Alarm Siren.
Disconnect Car Battery (sorry about radio settings).
Disconnect ABS Fuse.
Disconnect ABS ECU Harness. The orange lock lever is quite tight and you need to pull it up.
Connect CB.
Start – if it starts. ABS dash light will stay on obviously.

BTW, so far have managed to test the Fuel Pump independently (took some time to be 100% of the wiring). Worked ok. Also tested ABS ECU incoming signals and Wheel Sensors. WS are ok regardless of the existing err codes indicating that they’re not! But there is lack of comms at pin 14 (at ABS ECU) which is for Diagnosis Changeover Input. Next task is to study where that data comes from…

 

[Tappara]

Update.
So far tested that Fuel Pump works ok, with external power.
Therefore suspected Fuel Relay. Took a while to locate it, no tnx to insufficient or bad info. Finally discovered that the FR works ok once its pin 2 (W-R wire) is Earthed to chassis and others remain connected to FR harness with Jumper wires (had to make some). Normally that FR Pin 2 is Earthed by ECU via its Pin 22, but it's obviously not doing so.
And considering even now when FR and FP (fuel splashing wildly in the pipes) were running ok, engine didn't fire. So it starts to point to an Immobilizer issue - which could be very well caused by the after market Alarm connections, but cannot ascertain this until further research is conducted.
Where is the Immob - anyone? I know it's in the dash area like the FR is, but an exact location (and device description) would save me some time.
All fun!

 

[hozza]

I'm not sure if these cars came with a stock immobilizer. So if it's an after market one lie on you back on the drivers floor. Generally there will be a black box or some thing. They will be tapped into the indicators near the indicator selector and also the door Locks in the bottom right of the drivers foot well.

 

[Tappara]

Problem found and rectified.
Had to call a guy with correct tools and skills to chase this issue.
Don't wanna blame anyone, so will make it bit vague..... It was a connection causing some havoc with Immobilizer and ECU.
But the ABS errors and lack of ECU errors still baffle me - I thought they would be quite comprehensive. But there we go, we learn.
It was nice to drive it for a change!
Thanks to all who gave me hints.
I have nothing to do now, what should I plan next....?

 

[hozza]

Glad to hear. Yeah some times its best to just let the professionals do it.
Drive it? lol

 

[Tappara]

Weeellll, even tho I said I don't want to start a blame game, it was the fault of the professional at the end.
You suggest driving it for change? Ok, shall do so!!!