Aux fan matic function not working

**m83x** · April 22nd, 2006 02:45 AM

Guys, have problem with my Civic Esi 93.. Before when I start the engine, nag automatic ON din ang aux fan ng radiator. Ngayon hindi na.

What I did was, pinag-short circuit ko yung connector as engine para umandar yung fan, safe na yon? Kaka-replace ko lang din kasi nun kasi nangyari na sa akin dati yon kaso umulit ulit.

Thanks in advance guys!

**Betz** · April 22nd, 2006 08:22 AM

Baka sira na ung Thermo switch, have it checked.

**corbon44** · April 22nd, 2006 12:39 PM

Originally Posted by m83x

Guys, have problem with my Civic Esi 93.. Before when I start the engine, nag automatic ON din ang aux fan ng radiator. Ngayon hindi na.

What I did was, pinag-short circuit ko yung connector as engine para umandar yung fan, safe na yon? Kaka-replace ko lang din kasi nun kasi nangyari na sa akin dati yon kaso umulit ulit.

Thanks in advance guys!

Ideally, the aux fan SHOULD NOT turn on automatically upon starting - it would depend on the temperature of the engine/cooling system, regulated by the thermo switch mentioned above.

It is a common quick fix to directly connect the circuit to the ignition so the fan turns on once the ignition is switched on.

There would be at least two concerns why this is not recommended:

1.) This is an AUX fan - it was not designed to run all the time, so running it as long as long as the ignition is on would shorten its motor's life (take note, a new fan motor ranges from 2.5K - 3.5K).

2.) An engine requires an optimal running temperature, running the fan immediately upon starting the engine would lengthen reaching this optimal temperature level. Running at the optimal temperature would be beneficial in terms of fuel economy and engine performance.

The thermo switch is usually located underneath the radiator. It can be removed with a wrench (no. 12 or 14?), though this would drain the coolant as well.

Once removed, it can be tested with a circuit tester and a heat source (probably a lighter or small torch). With the switch attached to the circuit tester, heat the probe with the lighter and observe if the circuit closes or not. A defective switch would obviously not close.

If defective, a replacement only costs around P400 to P600. Just screw back the replacement, connect the terminals and refill the coolant. Run the engine. The fan should switch on in a couple of minutes.

HTH.