T350 Speedo Problem

[GaryF]

Excellent.

[Jez-hacp7]

Hi all,

There may be a more recent posting on the subject, but I can't find it - I'm having some issues with the LCD dash readout in my T350c - I'd like to start by changing the ribbon cables, but can't find the details - the one link I found in another thread is no longer active - can anyone assist?

[pb450]

Hi there, OP here.
My specialist did both of mine in half an hour. I watched but didn’t help. What exactly do you want to know?

[JezNH]

Hi,

The analogue dials are fine, it’s the lcd panel, it regularly freezes and only updates every 30 seconds or so, either 2 Or 3 of the gear change lights are permanently illuminated, and it takes a long while to initiate on startup - occasionally the screen is corrupt during the startup process. It seems to be a loose connection or cable issue as it is generally brought on by bad road surfaces, and sometimes a second jolt will bring it right…. For a short while.

TIA

[JezNH]

Oh, and when the lcd panel is misbehaving the heater and fan controls generally join the party!

[pb450]

Replacing the ribbon cables is a pretty cheap thing to do, so personally I’d start with these and see if replacement solves your problems.
If not, it sounds like a dry joint somewhere. Don’t scrimp on cheap ones as I think the genuine TVR items were less than £10 each. Good luck.

[Granturadriver]

But maybe the cables are just loose. Then strange reactions also appear, like "holey" displays or flickering and so on.

The instrument cluster is attached with two screws from below. They are located on the left and right. Once they are loosened, the entire part can be lifted off and the cables can be checked.

The computer flat cables are nothing special. They can basically be assembled from individual parts (cables and connectors) from any computer parts store.

[Adrian@]

The earth in the passenger foot well...might well cause this issue. The internal bolt locks into a threaded brass bobbin, BUT then when the nut that locks the cables above the battery (the other side of the shell) spins the bolt loose as it is done up, leaving the internal cables factionally loose (if this done as a one man job). A@

[JezNH]

Thanks for the advice all. I’ll remove the cluster and check the cables, and also the earthing point. Will look to replace the cables, would rather buy than make from components if I can source them reasonably @pb450 any idea where they can be bought from?

[pb450]

https://powersperformance.co.uk/store/slug/ribbon-...
They’ve gone up a little since mine a couple of years ago. I expect Racetech also have them but I couldn’t find them on a quick search. The guy there is really helpful if you call.

[MK_tamora]

Also available from partsfortvrs and a bit cheaper with a tvrcc discount.

[JezNH]

Cables ordered from Motoclan (formerly parts for tvrs I believe), hopefully that does the trick. I’ll post an update when fitted. Thanks again!

[pb450]

Curious to know if this solves your problem. Do please report back.

[JezNH]

Brief update….. cables arrived, did the contortionist act required to get to anything footwell related! Located the dash ECU, basically it is not attached to any part of the car, and it’s full weight is dangling on the end of the cables (the door ECU is in a similar state), hardly surprising the cables were not seated properly. It seems this is the issue as it behaved on a 25 mile test drive. I will replace the cables, as I have them, but will do when the time permits a proper fettle.

For now it is sorted and will allow me to get to the TVRCC season opener at Burghley House tomorrow without worrying about anything instrument readout related. See you there if you’re going. And thanks again all for the help and advice!

[pb450]

Really glad to hear you’re sorted. I won’t be there unfortunately but it’s a great event. I was there last year. Have fun.

[Granturadriver]

The control units all belong in the niche on the right in the footwell. They are attached to the carpet on the wall or to each other with Velcro.

A cover plate belongs in front of the niche, which is also attached to the edge of the niche with Velcro.

[JezNH]

Granturadriver said:

The control units all belong in the niche on the right in the footwell. They are attached to the carpet on the wall or to each other with Velcro.

A cover plate belongs in front of the niche, which is also attached to the edge of the niche with Velcro.

Thanks, seems I need to get some velcro tape, there is no evidence/ remnants of any! The cover plate is there, but this too is unattached - someone did a piss poor job of sorting it out at some point