Code 42 Fix

Well I'm really confused now. How can the PAS,Cruise Control and Active Spoiler work correctly when their signal wire (pink) is cut and not connected to anything?

 

I don't see how joining the pink to the input achieves anything if the pink is the output from the odometer.

 

Is there another output to the PAS, Cruise Control and Active Spoiler?

I agree. I'm glad that it works for you Dave, but I can't see how! I think the ECU, PPS, cruise control etc is all "downstream" from the wire that comes out of pin 6 (the pink wire in the diagrams), but this wire is left floating.

I haven't found the circuit diagram at home that confirms the input/output pins of the odo plug: will have a look in the next couple of days, but I'm pretty sure that I'm right about pins 5 and 6.

well i found this fix on here cant remeber where .but i havent got an active spoiler or cruise so i cant comment on how this would affect those systems .if you find any other way of doing it please let me know by PM. my steering seems to function ok havent noticed it going light at speeds

You wouldn't notice it getting lighter because the PPS is already light at slower speeds. The question would be: Does it get heavier at speed as it should?

I definitely want to know whether or not the PPS and active spoiler still work with this pin 5/6 snip and fix.

Has anybody made any headway on this issue? I am going to pull the dash tomorrow in hopes of fixing the code 42 and delimiting the car. If anyone has figured out how to fix/bypass the buffering signal to/from the odometer while keeping it functional, please chime in.

Sorry JSpec, I tried to find the documentation that came with my Thor DSC+TSD but couldn't find it.

so are we no further on with this, i agree if you do the fix it will solve the flashing lights problem as the ecu will not get the signal, however i think you will loose the active spoiler and pps and cruise control. is it worth doing that to just get rid of a light?

however when code 42 comes in does the ecu go to some sort of safe mode and shut them off anyway????

or is there another feed to the pps etc from another speed sensor?

I can't comment on the active spoiler or cruise control because I don't have them on my car. AFAIK the ECU only needs a speed signal from the odo unit in order to maintain the PPS. It doesn't matter if that signal is buffered by the odo unit first (i.e. stock wiring) or unbuffered (i.e. the modification that I suggested).

If it were me, I would do the modification to fix the code 42 problem. The engine warning light by itself isn't really a problem, but if the ECU logs another more serious fault, you'll be none the wiser because you'll either have pulled the bulb out of the warning light, or just be ignoring it anyway thinking "I can ignore that, it's just code 42".

I'm not aware that the ECU goes into a safe mode. I think it's up to the driver to respond to the warning.

The worst case is that the change I suggested doesn't work, in which case you could splice it back together. Not great, but it means that the change isn't totally irreversible.

Hope that helps a bit.

where does the ecu get its other signal for pps from mate? there isnt one on that diagram which was my point?

Sorry about that, I think this is what you need to do. Referring to the odometer plug, cut the wire to pin 6. This is the buffered output that isn't working any more. Strip some insulation from the wire to pin 5 (but no need to cut it), and solder the loom side of the pin 6 wire to it. This means that the speed signal flowing along the pin 5 wire will reach both the odo internals, AND be re-distributed to the PPS etc.

I think the PPS picks up its signal (possibly via the ECU which you shouldn't need to touch for this job) from the loom side of pin 6.

My PPS was overreactive and my odometer and blitz id meter werent working anymore. I did the trick as described above. It removed the warning light and it fixed my PPS. It works fine now. But my odometer isn;t counting, is there a way to solve that?

so what is the pin 5 wires function? if his odo isnt working is it the signal for that. if so its not a very good solution is it

My PPS was overreactive and my odometer and blitz id meter werent working anymore. I did the trick as described above. It removed the warning light and it fixed my PPS. It works fine now. But my odometer isn;t counting, is there a way to solve that?

Are you certain that you haven't cut the wire to pin 5? You should have stripped the insulation from the pin 5 wire (so that you can solder the pin 6 loom-side wire to it), but not cut it.

this is very confusing, some people say cut and splice from the plug side of the pink wire and some say as above to splice from the loom side????? whats the correct way??? i could fathom it if i knew the function of pin 5 (blue and red wire)

AFAIK pin 5 is the input signal to the odo unit, and pin 6 is the output. When you get a code 42, it's usually the output of the odo that has gone wrong, hence the need to NOT cut the pin 5 wire, and put the pin 5 wire's signal onto the downstream (loom-side) pin 6 wire.

yeah that sounds correct, but doesnt the odo bufffer the signal? if you re route the signal ie unbuffed it will still send out the same dodgy signal

Are you certain that you haven't cut the wire to pin 5? You should have stripped the insulation from the pin 5 wire (so that you can solder the pin 6 loom-side wire to it), but not cut it.

oeps

i have cut the pink wire and placed te loom-side of the pink wire to the blue/red wire

oeps

i have cut the pink wire and placed te loom-side of the pink wire to the blue/red wire

That sounds correct to me. The pink wire goes to pin 6 (hence the odo output) and the blue/red wire goes to pin 5 (hence the odo input). As long as you haven't cut the blue/red wire, I would have thought that would work OK. If it *still* doesn't work, then maybe we've got pin 5 and pin 6 the wrong way round. I've based my suggestions on the TRL diagram that appears on one of the posts in this thread, but there's a smaller diagram also in this thread that appears to suggest the input and output are the other way round. If that's the case, then I'll be as surprised as you are.

What this solution tries to do is to bypass a faulty buffering circuit within the odo unit. I have never seen an explanation as to why the odo buffers the signal at all. Most of the good TSD units you can buy actually bypass the buffer circuit themselves. I've bypassed mine when I had a code 42 a couple of years ago, and it has worked properly since then (including the odo display incrementing as it should).

Alan: it's the buffer circuit that's probably faulty, not the input signal to the odo. If you accept that there's no need for buffering (you'll either have to take my word on this, or not as the case may be! See above), then joining the loom-side output to the still-continuous input wire means that 1) the odo should still receive the input signal it needs in order to increment; 2) the rest of the car should receive the signal that it needs to properly control the PPS etc and to eliminate the code 42 error.

yeah this is the corrcet way to re route away from the buffer circuit within the odo. only thought i had was if the ecu still had code 42 if the signal was not buffed? trial and error i guess

I noticed my wires had been fettled with behind the odometer... now I know why.

I think that's because you're trying to feed two signals to the ECU on the same wire, which it won't like. One signal from the odo output, and another from the odo input.

 

 

Not sure how the odo gets the speed signal input if you've done that. It can only get it from pin 5, and that's been cut and joined on the loom side to the output. This would allow the ECU to get the correct speed signal, but does your odo still count up as you drive?

since i have done this i have had no problems everything works odo - speedo etc. and no flashing lights

Interesting.

 

And approximately at what speed do the lights come on? 50-60-70mph

 

I have noticed mine come on at 55-60mph (when accelerating reasonably hard) and then when I reach 85-90 they go off. And when I slow down to 20 or to a standstill the lights ALWAYS go off.

 

This doesnt happen everytime though...only sometimes.

Mines now compeltely fixed by Mr Harwood and Thor.

Mines now compeltely fixed by Mr Harwood and Thor.

what did they do then imi???

Matt reinstalled it again, removed all the "scotch locks" and fitted another Thor converter.

Hi, hope this can be of some help to people. (It's already been mentioned above but hopefully this will clarify things)

I had lots of problems with my odo & speed sensitive steering etc. See this thread http://www.mkivsupra.net/vbb/showthread.php?t=89041

I tried Dave's Code 42 fix;

FIX:Take off the top part of dash and remove multi-plugs .On the one that goes into the odo you will see a pink wire and a blue/ red wire. r/h side of plug. join the pink wire from the multi plug to the red/blue wire , and the other end of the pink wire that comes from behind the dash just blank off.

This didn't work for me. I still got the warning lights & code 42 and the power steering stayed very light.

I joined the pink wire from the loom side to the blue/red and my speedo was all over the place.

After reading the above post i didn't bother trying this as i just assumed it wouldn't work and would mess up my speedo. After trying everything else possible i lost my rag, tried it, and now my car works perfectly fine. No error 42 and the progressive steering works fine, as it should. I was over the moon!

I'm not saying that Dave's way doesn't work (because it has for him) but i suggest trying both ways of wiring before moving on to something else! I wish i had! (it only takes a few minutes whereas re-soldering every part of the circuit board doesn't! netiher does removing your speed converter and re-fitting it! Doh! )

Recap - The method that worked for me was joining the pink wire and the blue/red wire (behind the dash) and then only having the blue/red wire connected to the plug going into the odo. The pink wire going into the odo plug should be cut. This sends the speed signal straight to the ecu down the pink wire and the info needed for the odo goes in through the red/blue wire. (this has been mentioned by stevie b above )

I have made a quick diagram in case my ramblings make no sense;

I just hope this helps people to fix the problem a lot quicker than i did!

If your odo ticks up the miles or kms OK, then you can be sure that the speed signal reaches as far as the odo input

I have a code 42 error im trying to track down at the moment. My MIL light comes on at 60mph, regardless of revs/boost. I have an active spoiler but its unplugged @ the AS ECU.

I've just wired in a replacement speed converter and still get code 42 @ 60mph.

My Odometer still increments the miles, so does this mean the speed sensor is OK and that the most likely culprit is the Odometer circuitry?

If thats the case I'll just see if JezzyBabes has a spare Odometer lying about.

Cheers

Simon