I just learnt about the ECU relearn !

[se13allmylife]

Thanks to all the defenders of my grammar , though for a minute I did doubt myself ! In reply to Harpoon's question , that is the way it was described in the data sheet and I took it to mean the same as you . I just pulled away as normal i.e. so the trans changed up at about 2500/3000 revs then held it in top for about 1/2 a mile (not easy in London) and that seemed to work for me . Still had to lift the bloody bonnet (hood) today 'coz like a berk I dislodged No.1 injector plug when I put the original spark plug back in , dduuurrghhh . Also forgot to mention yesterday when I disconnected the small white vacuum pipes I split the black connecting piece , whilst I was making it good I noticed the pipe felt hard in the middle . I passed a piece of wire through it and after about an inch it jammed solid , no amount of flushing and poking would dislodge the crap so I replaced it . If I hadn't broke the damn thing I would have overlooked this and even though there was no apparent ill effects I guess it must improve something , somewhere . If your interested mine was the pipe of the inlet breather nipple !

[misha]

What does 20/50% throttle to reach top gear mean? Does it mean give vehicle 50% of the gas pedal until you have gone through all the gears?

Yes.

[div4scpro]

A little confused. Do you need to disconnect both cables to discharge residual? I have now read negative, positive, and both. Clarification greatly appreciated.

[jblackburn]

Depends how you go about it discharging it. All you need to do is break the circuit and drain the charge.

The negative cable will do for my method (brake pedal/ignition key) or the waiting 15 min.

If you touch the cables together you'd disconnect both. We all know what happens when you touch live jumper cables together.

[MrSandman]

Hi, any advice on the next step would be greatly appreciated.

I recently did the ECU hard reset by removing the negative terminal of my battery, and then tapped the brake pedal a few times before re-attaching the negative terminal. Once all was back connected, and I had power back to the car, started up fine, all the lights work, the radio is now not functioning and the screen that once displayed the stations now reads "off". Any advice on how to get back to a normal working radio would be great. The car is a 1994 850 turbo wagon. Thanks in advance.

[LabRat]

^^^ See this thread: https://www.matthewsvolvosite.com/forums ... radio+code

[Pianoman702]

Not to thread-jack, but GET OUT OF TOWN!

So with my '96 850 turbo I disconnect the negative cable and press on the brake a few times with the key in OFF?
Reconnect and start.
Idle in P until warm.
1 minute idling in N.
1 minute idling in D.
50% throttle to top gear (like 2200-2800 rpm).
Brake to a stop.
Drive home.

And viola!?

I wonder how many of my Volwoes this could solve?

But in all seriousness, what I have listed above should work without any electrocution of me or my car?

[850_GLT_Owner]

So the IPD relearn procedure(for a new BCS/TCV)does something similar to this, but for the ECU to learn how to boost properly with turbo. Should they include a one minute idle in N and D?

From the IPD HD TCV install information:
"After the installation of the ipd HD TCV drive the vehicle for 5 minutes without developing any boost
pressure to allow the engine to warm up. In a safe and appropriate place, accelerate the vehicle
to approx half of its maximum boost level and hold there for 5-7 seconds, then decelerate to below
30mph. Proper accelerator modulation will be necessary to control the boost level. Repeat this 4 times.
Turn the engine off and wait for 12 minutes. For optimum results the above procedure should be
performed twice."

Any ideas on a modified version that would cover both? If i use the IPD procedure will it result in lower MPGs or should I use the method described in this thread first, then try the IPD procedure? Or would the procedure mentioned in this thread cover the half max boost portion of it as long as i stay between 2000-2800 RPMs?

[Fish stick88]

Thinking about doing this... Disconnected my battery about 2 months ago to install some subwoofers. All that really needs to happen is 15 mins of no power? and then try activating some power, to rid the circuits?

[ChiNorm]

Will removing the ECU from its terminal socket also trigger a re-learn(t)?

Thanks.