Phil Marino wrote:
> HI, Mark
>
> I've set up my Echo the same way ( using the AC switch to control
> the heater) so I'm familiar with the wiring.
>
> The fan takes a lot of current on high (about 12 amps) , so I can
> think of two possibilities:
>
>
> 1. Your 12V system voltage is dropping enough to drop the relay
> out. Put a voltmeter on your 12V system and watch the voltage as
> you change the fan speed.
>
> 2. There is enough voltage drop in the AC switch or wiring to
> allow the relay voltage to drop when the fan is on high.
>
> To check this, put a voltmeter on the relay coil and watch as you
> change fan speeds.
>
> What relay are you using?? It could be that the AC switch itself
> is the culprit - it's only designed to send a signal to the A/C
> amplifier, not power a large relay directly.
>
> Mine is set up so that the AC switch only drives a small ( 17 ma
> coil) relay , and THAT relay drives the larger KUEP relay ( 100 ma
> coil). You could try something like that.
>
>
>
> A third possibility ( this seems unlikely to me) is that the blower
> switch is faulty and is not grounding the heater relay ( which
> needs to be on to power the AC switch) when teh blower switch is in
> the "high" position. Or, if the ground wire from the heater switch
> were loose, it might have that same effect (because there is more
> current through that ground wire when the fan is on "high").
>
>
> Phil
>
>
>
>
>> From: Mark Dutko <
[email protected]>
>> Reply-To:
[email protected]
>> To:
[email protected]
>> Subject: Heater Relay Dropout Issue
>> Date: Fri, 27 Jul 2007 06:49:38 -0700
>>
>> I have my heater relay for my 220V pack grounded on one 12v side
>> and the other going to the positive wire of my heater fan through
>> a switch in the dash which used to be the AC switch, When the AC
>> switch is on and the fan is turned on the relay makes contact on
>> the first, second and third fan speed position but on the fourth
>> position or the highest, the relay drops out and I need to turn
>> the fan off to get it to contact again. I have a diode across the
>> relay coil (not sure if needed) and that's it. Any suggestions as
>> to a fix for this and why it happens on the high fan speed setting?
>>
>> Thanks,
>>
>> Mark
>>
>
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