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Old 01-13-2002, 11:53 AM
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Question Fuse 7 keeps popping

Hi, All

Today I lost all cold air entering the cabin (30 odd deg C today ...). I recently repaired the climate control system (was the aux fan relay, the aux fan series resistor and the dual valve being problematic ...) This was about 7 weeks ago and the system was in near daily use since then.

Anyway, I had a look and fuse 7 was a gonner. Replacing it got cold air in to the car but only for a minute or so. It popped again.

The aux fan starts and the electromagnetic fan kicks in as required. After a while (with the aux fan running) the fuse starts to show signs of distress before it fails.

I suspect the aux fan itself drawing too much current but still have to prove this by measuring the actual value.

Any ideas ITMT ?

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Old 01-21-2002, 04:33 AM
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An update

I replaced the fuse and disabled the air con (Economy mode). With this the AUX fan came on when the engine temperature demanded and the fuse stayed in tact.

After about a week I decided to use the air con again (after getting a number of spare fuses) and all went OK. No fuse 7 popping any more.

This is weird and I'm keeping a close eye on the situation.

dunno .........

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Old 01-22-2002, 09:49 PM
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Join Date: Jul 2000
Posts: 638
Why doesn't the fuse blow all the time

The system voltage may be dropping. Check the connections for tightness and corrosion. Even very light corrosion on the screw and plug connections is enough to cause this problem.

Check the battery terminals, and battery condition as well. Low voltage will increase the thermal load on the fuse because the fan motors will draw more amperage.
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Old 01-23-2002, 02:08 AM
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Thumbs up

I kinda discounted the issues you mentioned as there is only two connections in the aux fan circuit:
the connector towards the wiring harness at the fan itself, and the series aux fan resistor in the right hand front wing (belwo the ABS unit). Both were OK based on previous work carried out when fixing the darn thing ...

The aux fan relay was burnt out (one of the cuases of my original woes with the climate control) and I thought I had a recurrance of that episonde ...

I'll confirm battery voltage in any case, as well as the mentioned connectors.

Thanks for the reply
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Old 01-26-2002, 01:37 PM
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Fuse 7 update - fix !!

Here's an update to my Fuse 7 saga.

I did not think the issues were related ...

At about the same time as fuse 7 started to misbehave, the temp indicator in the car started to show a high reading (i.e. cold engine would indicate a 100 deg C).

I focused on the temp display and after a lot of testing, I decided to spend the $$$ to get a new temp sensor.

Replaced it and the temp indication worked 100%.

I noticed something loose on the removed temp sensor - it is a combination temp sensor and 100deg C elctromagnetic fan switch.

I dismantled the assembly and found that the switching mechanism for the fan was broken and was interfering with the operation of the temp sensor part - and causing intermittent short circuits - popping fuse 7 ...

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