Michael Benno

My car is chock full of interesting and probably time consuming mods and curious ways of doing things. Stuff like red painted parts all over the place. Stainless hardware on many things that need grounding, wire wrap intended for home stereo rather that high temp under hood, there are many many more. I have had a steady stream of parts sold or given away. It a good story and I should probably write it down.

Anyway, here is the latest in cleaning out the cowl I noticed this 3Amp fused line between the A/C Freeze Temp switch and the wire harness







I should add that this car has had the HVAC Relay Mod, I am not sure if this was related.

Any idea why this fuse line is in there? is it a failsafe to protect the switch? Is it related to the HVAC relay mod? Any concerns about omitting this and reconnecting the original line (which i did).

PS, my HVAC system is working fine.
PPS, Yes I removed the weird home stereo cable management stuff in there as well. More PO undoing.


Thanks.

The Forgotten On

The PO may have just added that in there in order to add a fuse to the circuit, otherwise the relay isthe fuse, or if that doesn't work, the PCB in the HVAC head burns up.

They also could have done the relay mod (doubt it unless they were rennlist users). The only way to confirm this though is to pull the hvac head and look for anything suspect.

voskian

Per Dwayne's HVAC relay repair DIY...

"Since we replaced the smaller relay with a much beefier one rated at 10A which is much higher than the original 2.5A relay and the fact that the A/C compressor coil circuit is unfused between the HVAC head unit and the compressor, we must insert an inline fuse. The inline fuse will prevent circuit overload and the possibility of fire. The fuse will be inserted on the power line going into the freeze switch (this is a direct line from the HVAC head unit from the new relay). The recommended amperage of the inline fuse is 3A. I’d like to thank Greg Brown (GregBBRD on Rennlist) for this important addition and added protection from possible fire"

Looks like PO might have replaced the HVAC relay. Probably should leave it in there

Michael Benno

Cool thanks, sounds like there is a reason after all. I'll add it back in.

Mrmerlin

FWIW put the fuse assembly back into the freeze switch,
its part of the upgraded relay in the HVAC head.
This will protect the new relay from damage