rev4 turbo speedo issue

[pope_acute]

Ok, i have done some research but not finding an answer.

My speedo slowly started acting up and then not working at all. I have a converter/delimiter on the back of the clocks, it still does the power on self test which seems to work, but then the needle starts bouncing all over the place whilst not moving. So i removed the delimiter, and the clocks are dead totally no movement, got a replacement gearbox speedo sensor fitted it still not working... I was thinking of following this guide and testing the circuit board :

https://www.youtube.com/watch?v=G7qzfjwzT14

but i'm looking for what else i can check? before maybe buying a replacement cluster?

Was even thinking of sticking the unit in the oven, it's worked for my gfx cards in my pc's for years, to try and get the solder to rejoin..or would that be a bad idea?

also getting ecu code 42 as you would expect: vehicle speed sensor signal no speed signal for 8 seconds to ecu.

[pope_acute]

help kinda going round in circles here.

summary:

1: speedo no working, stef's delimiter fitted making needle jump all over and clocking miles while sitting still

2: removed delimiter, no speedo movement at all.

3: replaced with second hand working gearbox speedo sensor, old speedo sensor all white gear teeth intact no damage.

4: tested with new speedo nothing on clock, replaced stef's delimiter and the needle starts to jump and miles start to move while sitting still and driving.

i have it dismantled and am about to place it in teh oven just to see if that will work or not.

Just looking for anything else i can try before that.

ta

[pope_acute]

who's got a 180 mph working cluster for sale? lol

um..left it in the oven too long some of the smaller plastics melted, but the bigger plastics are fine, tried it anyway still no speedo...




if salvador dali did speedos....

[MartinF]

I'm really confused. why on earth did you put it in the oven?

When you say you removed the speedo converter did you re-connect the speed signal wire?

[pope_acute]

i tried the oven thing as its work for me before with gfx cards for pc's. stripping gfx card down to board, then reheating the circuit board reconnects the solder and gets it going again...but not this time.

not sure what you mean speed signal wire? the one on the gearbox? or the purple white cable behind the cluster on one of the connectors? both of those are connected.

[MartinF]

The reflow temp of solder is around 200degC, for plastic its a lot lower. When PCB's are flow soldered in factories they are generally done with no plastics on the board.

The speedo converter interrupts the speed signal going to the speedo and reduces its frequency to 5/8's of its original. So assuming it's your speedo converter that's at fault if you reconnect the speed signal wire, bypassing the converter, it and your speedo starts to read in KM's then you would just need to source a new converter. I believe the wire is purple and white that is interrupted by the converter but somebody else should hopefully confirm.

[Martin F]

who's got a 180 mph working cluster for sale? lol

http://www.imoc.co.uk/forums/viewtopic.php?t=183742

[pope_acute]

The reflow temp of solder is around 200degC, for plastic its a lot lower. When PCB's are flow soldered in factories they are generally done with no plastics on the board.

The speedo converter interrupts the speed signal going to the speedo and reduces its frequency to 5/8's of its original. So assuming it's your speedo converter that's at fault if you reconnect the speed signal wire, bypassing the converter, it and your speedo starts to read in KM's then you would just need to source a new converter. I believe the wire is purple and white that is interrupted by the converter but somebody else should hopefully confirm.

Yeah I find 195 degrees for 5 mins usually does the trick for gfx cards...but so didn't think about the smaller plastic bits. The bigger plastic bits of the housing were fine. Quite a silly thing to do really,ah well.


With and without delimiter not working properly. With delimiter I get needle jumps. Without delimiter I get nothing at all. Stef's delimiter does power on self test and that works. Where it goes 40 80 back to rest.

I thinking jacking up car spinning wheels and see if I can get a pulse reading from pins on gearbox sensor. The replacement sensor maybe at fault. I bought it as working online but never tested it

[pope_acute]

who's got a 180 mph working cluster for sale? lol

http://www.imoc.co.uk/forums/viewtopic.php?t=183742

Thanks for that link,but sourced some already.

[gavsdavs]

i tried the oven thing as its work for me before with gfx cards for pc's. stripping gfx card down to board, then reheating the circuit board reconnects the solder and gets it going again...but not this time.

I would be amazed if that had the desired effect. Have you seen what cheese does when you put it on bread under a grill? It doesn't melt in an orderly way......

[danjama]

I put my PS3 mainboard in the oven for 15 minutes after it had a yellow light of death or whatever it is.

That was 3 years ago and it's still going strong.

So, the oven trick can work.

[danjama]

I put my PS3 mainboard in the oven for 15 minutes after it had a yellow light of death or whatever it is.

That was 3 years ago and it's still going strong.

So, the oven trick can work.

[Rob]

Use electrical contact grease on the loom clip that attaches to the speedo sensor / drive. Totally fixed my problem that sounded exactly like yours.

[pope_acute]

Use electrical contact grease on the loom clip that attaches to the speedo sensor / drive. Totally fixed my problem that sounded exactly like yours.

thanks i'll give that a go when the cluster arrives...

I put my PS3 mainboard in the oven for 15 minutes after it had a yellow light of death or whatever it is.

That was 3 years ago and it's still going strong.

So, the oven trick can work.

yeah i have done a few of those too for mates. only had one back that failed again, repeated process and that sorted it.

I would be amazed if that had the desired effect. Have you seen what cheese does when you put it on bread under a grill? It doesn't melt in an orderly way......

i know sounds daft but does work, just not on dials, well not the way i did it anyhow. hmmm cheese on toast...

[pope_acute]

ok, so i found the issue out, thought i'd share, decided to strip back the loom and found 6 soldered connections of which 4 had cracked and spilt. No idea what happened there or what the previous owner did, but had the two for 6 years now and only finding this out now.

So yes, i could have saved my self a lot of hassle and money(second speedo sensor and clocks) if i had done that first. anyway striped out the crap created new cable with new connections and viola speedo is now working. ....sort of.

got anew issue now, seems to be running 13mph roughly behind actual speed. 5th gear 3k rpm, 40 mph on clock but gps is stating 53mph.

when putting the needle back on tot dial face, i twisted the centre and place the needle on asap to that it would return to rest quicker. could i have twisted two far and and it too tight for it to read accurately.

i have steph's converter on the back of the clocks and little switch set to mph not kph, .that's right isn't it? lost instructions a while back.

[thomp1983]

If you've had the needle off then it's out when you put it back on. I normally drive it at 30 get the mrs to hold the wheel and put the needle back on it's awkward but about the only way. i usually get it within 2-3mph upto 50 and around 5mph out at 70 which im happy with

[acf8181]

If you've had the needle off then it's out when you put it back on. I normally drive it at 30 get the mrs to hold the wheel and put the needle back on it's awkward but about the only way. i usually get it within 2-3mph upto 50 and around 5mph out at 70 which im happy with

unnecesary to take that risk

you'll be pretty close if you do this...

-start car (needle pops up normally)
-place needle on with it pointing towards the corner of the light below the speedo
-gently edge needle over the stop

...then test drive with gps to check its accurate. i had it right first time whe i did it!

[thomp1983]

-place needle on with it pointing towards the corner of the light below the speedo

could you expand on this abit please buddy

chris.

[acf8181]

-place needle on with it pointing towards the corner of the light below the speedo

could you expand on this abit please buddy

chris.

excuse my basic paint skills...

[Pauln]

If your still using the Steph delimiter can you not use the test mode to reset the needle correctly. From memory I think it sweeps to 120, then 60, then 0.

Just a thought.

Paul