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shantillylais
28th July 2017, 12:04 AM
Hey there guru's :)
I am installing my pillarpod and have VDO pyro and boost gauges.
All pretty straight forward EXCEPT for the 5metre extension loom they supply for the pyro thermocouple. It has terminals on the thermocouple end, simple enough. But the gauge end has no terminals, and none supplied in the kit. So natural assumption is standard spade terminals crimped style. I know that I cannot solder the joint.

My big question is, (and I have searched Google for an hour and read heaps), there is conflicting opinions about cutting the 5 metre extension lead. My instructions do NOT have any written "instructions" about that. HOWEVER, when doing my google search, I came across some VDO instruction sheets that definitely "instructed" DO NOT CUT.

At almost 6 metres thermocouple to end of extension, that means one heck of a loop in the wire under the dash.

What have YOU done? BTW, other gauge types/instructions are irrelevant. I have installed other brands before but without this extension lead/wire.
cheers
Lana

MudRunnerTD
28th July 2017, 12:31 AM
Do Not Cut. It is a Calibrated length. I just coiled mine up and zip tied it out of the way in the engine bay.

jff45
28th July 2017, 07:32 AM
Ditto, mine is coiled up behind the glovebox because I came through the firewall on the passenger side.

shantillylais
29th July 2017, 10:07 PM
thanks guys, but interestingly today, I received a email from the supplier (VDO service agent) that it is ok to cut. That is why it isn't terminated at factory before supply. Now I am really concerned, so I called and emailed VDO Australia, and waiting a response. I will keep you informed :) cheers Lana

GeeYou8
6th August 2017, 09:08 AM
I assume the VDO has some electronics in it so it is a high impedance indicator, so the total resistance of the thermocouple won't make much difference.
If it was an old school pyrometer that indicates temperature even when the power is off it would be powered by the millivolts produced by the thermocouple & therefore you would need to have the correct length/resistance.
In a perfect world the contacts that you crimp onto the wire would be made of the same material is the thermocouple wire, this is what they have for aircraft & the connectors are hellish expensive. As long as the crimps are right at the indicator where there is little or no difference in temperature from one side of the crimp to the other it will make very little difference.
Graham