2006 Exige S

This is where we proud owners can upload information and pictures of our pride-and-joys (their Exige that is..)
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andybond
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This is all interesting useful stuff!
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Fonzey
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I think I've got my first lead thanks to the test rig!

I've not been out in the car yet (rain!) but noticed when I was fidgeting around in the cockpit that if I banged the dashboard the multimeter report from the control wire would fluxuate...

I took this a bit further by popping the control panel off and then gave the wires at the back of the potentiometer a wiggle... et voila.



I'm pretty sure the voltage shouldn't be fluctuating so much like that. If I stick my phone into the access panel you can see the flap moving too.



(this is the flap moving from cold to heat as the wire is fniggled)

This feels like a bit of a slam dunk here. Trying hard to not get excited!

I've taken the potentiometer knob out of the dash (along with the blower position one that it's soldered to) and got it on the bench.

Image

There's a spare heater control panel on eBay currently so that's an option, but it's old and used and I've got no guarantees on it I guess. I imagine the potentiometers are available somewhere for pennies, but so far Google-fu is letting me down on the stamped part number - so more work needed before I can put a fix in.

It may just be the short length of wiring, or the quality of the solder to the board - so removing and refitting might be all it takes but if I can source a new knob I might aswell swap the lot out.
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thommo
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Exciting! (And I'm being serious here). Well done :thumbup:
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deggles
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Good work :)

Does look like just a bad connection/fractured wire from the video. You should be able to test the pot. is still working in isolation with the meter on the resistance setting. I reckon soldering a new length of wire on will be job = carrot :thumbup:
tlracer
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What are the numbers on the pot?

Pot testing:

a) Check span resistance (usually the two end contacts)
b) Put DVM on one end and middle, rotate pot and note if reading changes smoothly or not (NB. Pot may be linear or log, so don't be thrown if mid-travel isn't half the span)
c) Put DVM on other end and middle, repeat above

Pot tracks can be really bad for getting dirty. A good end-to-end wiggle might help, plus spray with contact cleaner (solvent-type only, usually IPA, not the oily stuff...)

Get a magnifying glass and check all the soldered joints on the pcb. We get bad/dry joints that look fine on a couple of lab meters we work on often, it's only with a lens that the fault is visible.
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Fonzey
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Cheers for the input team. Due to the nature of the 'wiggling' I do suspect the wires or the soldered connections rather than the pot itself - but who knows. I expected the pot to be a cheap and easily sourced part so I'd throw a new one in "just because" but I'm struggling to track down the part number.(45052013 0549) (Zero's could be o's and 5's could be S's tbh - hard to read)

Before I started on this journey the first thing I did was check resistance across the contacts on the pot, which came back as expected but of course it's very hard to measure this whilst manipulating the wires etc. I've just about managed to balance my multimeter probes against the contacts on the PCB whilst wiggling the wire and can see the same sort of variations in resistance as to what I see in voltage on the actual loom - so the pieces are all adding up.

I've given the inside of the pot a good blast out with contact cleaner just to cover all bases.

As for inspecting the solder joins.... well, fingers crossed I've found it already. No magnifying glass required:

Image

*disclaimer* there's half a chance that I broke that join myself whilst stripping off the heatshrink... but I'm kinda sure it was already loose inside there. The others are secure and snug but this one just fell straight out as soon as I stripped back the heatshrink.

Hopefully this is now a quick fix, solder in three new wires tomorrow with some fresh heatshrink and then try again with the wiggle test.

If anyone knows Neil at Lotus I wouldn't mind a chat about the thoroughness of his testing.

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andybond
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I have just chuckled at the Neil @ Lotus comment
tlracer
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... and this is why so many motorsport and other high-stress connections are crimped, not soldered :thumbup:
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Fonzey
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Bit of progress today.

Sucked the old solder out first and removed the wires.

Image

Pretty sure the wires are OK, but I've got some of the same gauge (but no pink, so brown will have to do :roll: ) so figured I'd swap it out anyway.

Re-soldered t'other end and got some new heatshrink on and we're ready for testing.

Image


The verdict... I can no longer get the voltage to fluctuate when manipulating the new wires or the centre control panel, it sits rock steady at 0.22V (a bit lower than before, so maybe my wire is a different gauge after all :oops: ) but still within operating tolerance of the flap it seems. Full cold = full cold, full hot = full hot and half way between is half way between!

Needs a good road test before I declare success, but for now the signs are looking good. Will get the front of the car put back together then find an excuse to go for an icy cold drive. 8-)
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andybond
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I wonder what I am going to be checking this weekend ...
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