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Can you get the gearbox mapped on a car running standard BHP ?

An is the map done through the TCU. I am trying to cure 2 codes I get that are 18223 and 18243 if the TCU is faulty was going to either get it repaired or buy another an get it mapped.

Would it improve the shifting and are there any negatives as I dont want to put any extra strain on.the chocolate gearbox

You can. There's not much to be gained. The shift points can be changed slightly, if that's something you want. On mine, the MTM TCU keeps the torque converter locked on throttle lift off which gives engine braking, which is nice. I wouldn't be without that now.

There are no negatives really, other than it might not be a good use of money if you're not mapped.

Your error codes relate to short circuits in some of the solenoids. What have you done to eliminate other causes than the TCU?

Replaced the harness in the gearbox so far.

Its odd as u start it straight away it won't show fault codes but turn it on leave it then start it will. This all started happening when my bonnet grommet leaked into car an it was soaking.

Sounds like the TCU might have got wet then.

I did dry it out at the time. I ve just checked again an its bone dry under there now but taken it out an left it by the log burner just incase.

I repaired a waterlogged ECU in a friend’s D2 S8 once. It was a Hail Mary job. Worked though. Had to reflow the solder joints and that did the trick.

I ve taken the top of the TCU an looked inside and some of the solder joints are orange ish in colour so think this could be the issue as the faults codes that appeared are around the same time I had a water leak through the bonnet cable grommet.

I ve take some pics of the orange joints.

Yeah, looks a bit corroded. But more importantly, those joints are cracked. You can clearly see.

Don't think it's corrosion, on second thoughts. Just looks like localised build-up of conformal coating, but it could also be flux residue, which can be corrosive. Some factories are better than other at cleaning it off. Those big pads just look like radiators.

Get a 20x jeweller magnifier and check all the solder joints.

Reminds me of the issue found on my spare TCU... surprisingly, it still worked fine, though!
(Pic taken just before I soldered replacement capacitors in)

Mmm. Bulgy.

That’s what she said

Iv got perfectly good working TCU available if needed

Shoppinit wrote: ↑

Sun Jan 28, 2024 8:04 pm

Mmm. Bulgy.

lolsie.

Took a punt on a second hand TCU which arrived today, fitted it an no more fault codes so fingers crossed its fixed.

Feel like it's drives better aswell but nor sure if it's just in my head.