Temp gauge

An alchemy of sparks, copper wire and earth

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AngeloEvs
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Re: Temp gauge

Post by AngeloEvs »

Update for those following this thread and curious as to the cause of the Temp Gauge moving full deflection and the Coolant LED continually flashing.   The Dash was placed on the bench and a Resistance measurement  taken across the Temp Gauge output before powering up - the reading indicated a short circuit across the Gauge output connection to Earth.   The SHC Kit uses PCB's for both the Fuel and Temp gauges to simply installation. 

The PCB for the Temperature gauge was removed and the fault was immediately evident - the three pin Connector pads were extremely close to each other.  The PCB Earth Connection and the Temp Gauge Output were close enough to create a short circuit.  
This may well have been an isolated or Batch production fault or it could be something that needs to be addressed in the choice of connection used.

The solution is to either return the PCB or simply knife the edges of the circular pads to create a gap.  Be aware that a prolonged short circuit across the Temp gauge will damage the pointer movement and no longer be accurate or the gauge may fail completely.



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Re: Temp gauge

Post by southernscouse »

I have been in touch with shc they have offered free of charge a set of nylon washers to isolate the circuit board I have already told them that no amount of nylon washers would cure the faulty circuit board it also will not help the fact that my temp gauge is now fxxxxd

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Re: Temp gauge

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Methinks their quality control needs sorting out. :roll:  
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Re: Temp gauge

Post by Aidan »

any fule could see the pads are too big/too close - very poor design and implementation, and judging by the printing on the board this is version 2 :roll: hopefully the subsequent version/batch is okay

Do SHC come on here ? It would be great to hear from them............I have yet to hear a good thing about these kits, just reports of problem after problem

I really don't see the need for the kit, most original flexiboards are repairable with some care, it's just peeps seem to want a quick plug and play alternative to fixing things, but the kits aren't cheap or completely effortless to fit - iirc SHC charge a couple of hundred fitted which is fine if you live down their way but for diy I am not sure it's a good thing

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Re: Temp gauge

Post by southernscouse »

Today I received this from SHC it came with a new lead and a set of nylon washers no mention about my fxxxxd gauge Image

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R0B
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Re: Temp gauge

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You need to tell them. (if you haven't already) They need to cover the cost of you sourcing a replacement.
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Re: Temp gauge

Post by silverbullet »

Aidan wrote: 06 Sep 2023, 15:37
Do SHC come on here ? It would be great to hear from them............I have yet to hear a good thing about these kits, just reports of problem after problem


The do a lot of "reaching out" on fb

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Re: Temp gauge

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Aidan wrote: 06 Sep 2023, 15:37 I really don't see the need for the kit, most original flexiboards are repairable with some care, it's just peeps seem to want a quick plug and play alternative to fixing things, but the kits aren't cheap or completely effortless to fit - iirc SHC charge a couple of hundred fitted which is fine if you live down their way but for diy I am not sure it's a good thing

Totally agree! I have removed 8 or 9 of these kits (Only one SHC) and refitted the original flex PCB for people. In many cases there was nothing wrong with the original PCB anyway, and not one of the faulty flex PCBs took anywhere near as long to repair is it would have done to fit the bundle of snakes kit in the first place! 

Unless the copper is torn where the main connector goes on, almost all other issues are pretty straightforward.

I'm a bit baffled as to why someone hasn't just replicated the original flex PCB now, it's easy enough to get them made in china and the bare pcb wouldn't be much more than £20 if you ordered a hundred. You could even just put an old PCB in a scanner and 75% of the design work is already done!


Back on to this one:
It looks like those solder joints have been crushed quite hard against something flat, causing them to spread out.

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Re: Temp gauge

Post by Stesaw »

Thanks for reminding me that I need to sort my gauges out as they throw a wobbly now and then.
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Re: Temp gauge

Post by southernscouse »

There is no way I could have bolted down the circuit board to flatten the contacts they were made wrong from the start have you tried to squash solder between two bits of plastic

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Re: Temp gauge

Post by cobblers »

southernscouse wrote: 12 Sep 2023, 19:25 There is no way I could have bolted down the circuit board to flatten the contacts they were made wrong from the start have you tried to squash solder between two bits of plastic

I wasn't suggesting you'd done it, but that's almost definitely what has caused this problem. The PCB would have been fine when manufactured, so maybe you ended up with one that a customer had returned? 

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Re: Temp gauge

Post by AngeloEvs »

The joints were not soldered, the socket itself is very thin plastic and the position and the amount of pressure needed to flatten all three solder joints would would have destroyed the socket itself. The pins appear to be pressed into the pads and their edges are clearly visible. I think this is some sort of PCB manufacturing or assembly error when the socket was inserted into the PCB.

The three pin header socket should have at least 1mm - 1.5mm of each terminal protruding from the solder side of the PCB and should not be flush with the pad. The protruding terminal pins and their correctly soldered joints can be seen in the photograph of the replacement board that SHC sent to replace the faulty one. Interesting that they also provided spacers which are needed to give a bit of clearance between the solder joints and the surface of the Dash Enclosure. These were not provided in the kit.
Last edited by AngeloEvs on 15 Sep 2023, 08:57, edited 1 time in total.
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Re: Temp gauge

Post by Mocki »

Are SHC not very closely “in bed” with brickwerks now ? At least that what i have seen opinionated on the inter web elsewhere ?
I agree most original foils and gauge sets are repairable with a bit of time and care …..
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