KingAir

Did a temporary install of my near completed extra gauge cluster
recently(volts, oil pressure, clock, water temp, oil temp),
I'll post up when all finished. All working well.
Yesterday going home noticed temp rapidly rising - 210, 220, 230..!
The gauges are reading accurately - I checked them all before install
and were good to around +/- 1% or so.
So my radiator fan is not coming on, fuse is OK, next thing I want to check
is fan switch. I want to remove the plug and just bridge across.
If the fan comes on the switch is dodgy.
Problem is I can't seem to remove the plug from the switch,
not the easiest to get to and can't feel/see any lugs that have to be pressed
etc. Any of you removed and can give me some advise about how this comes
off? Thanks Guys.

stevharr

Does the guage take it's temp reading from the same sensor as the ECU? If the guage has a separate sensor, it's possible that the stock one has an air pocket around it or the water is not circutating. You may need to bleed the system. This has happened to me every a few times. For a quick check - feel the top and bottom radiator hoses, they should both be hot - if the lower one is cool your thermostat is not opening. I would bleed the system anyway.

KingAir

Thanks Steve, I drilled and tapped the drain plug on the side of the
block to take the sender - just confirmed the fan switch is the problem,
so shall find another one or splice a manual switch in till
I can get one.

stevharr

Are you absolutely sure it's the relay? Since you've been drilling into the block, you almost certainly have let air into the cooling system.

KingAir

It's definitely the switch on the bottom of the radiator, no fan running
when hot, so open circuit all the time. If I bridge the plug the fan runs.
I didn't actually drill into the block.
I bought a new drain plug and drilled and tapped that and then installed
the sender unit.
When CRS last did my service I had them drain the coolant, install my modified
plug and then replace coolant.
Thanks for the input - it's appreciated. Cheers

stevharr

[quote name='KingAir' date='Jan 29 2009, 02:02 PM'] It's definitely the switch on the bottom of the radiator, no fan running
when hot, so open circuit all the time. If I bridge the plug the fan runs.
I didn't actually drill into the block.
I bought a new drain plug and drilled and tapped that and then installed
the sender unit.
When CRS last did my service I had them drain the coolant, install my modified
plug and then replace coolant.
Thanks for the input - it's appreciated.

KingAir

Not really sure on that one at all - I'm guessing the stock ECU would not switch
the relay- if that was the case I would think Honda would not have put the
radiator switch in at all.
Aftermarket ECU I guess gives you the flexibility of picking the temp
to turn the fan on?
But as I say I'm guessing totally here.