Citroen zx radiator fan to manual switching.

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Huskyxantia
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Skoda fabia,escort van,ford ka,Vauxhall astra g car & estate, Vauxhall corsa b, Suzuki swift
Escorts mk 1,2,3,4,5 fiestas mk 1,2, Sierra diesel mk1 Mondeo mk1 diesel .
Peugeot 207 , 307sw

Now cars
Picasso 2.0Hdi now gone to scrappie
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Peugeot 206cc raised from the dead & saved from the crusher traded up to a 308cc
307sw traded for the 207 .

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Peugeot 405 diesel
106 or 206
Mondeo Mk1 diesel once owned 1.8tdi was real nice.
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Citroen zx radiator fan to manual switching.

Post by Huskyxantia »

Took my old ZX estate 1994 today for its MOT. Its been off the road since 2017 and decided to take it for the test.

It passed.

I'm wanting to put the radiator fans on a separate switch .

How do you do this .

Any help
Thanks in advance :)
Husky. :?
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white exec
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and lots of Rovers before that: 1935 Ten, 1947 Sixteen, 1960 P5 3-litre, 1966 P6 2000, 1972 P6 2000TC, and 1975 P6B 3500S
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Re: Citroen zx radiator fan to manual switching.

Post by white exec »

Here's the standard circuit set-up for twin fans being controlled by the bank of three relays. The relays are energised by supplies from either a two-stage thermo-switch (early models) or from an ECU-fed temperature controller* (later models).
* Check polarity of this control signal, +12 or Gnd.

Either way, it is possible to manually turn on the relays (you just need to identify the Low and High speed supply lines) to give manual switching of the fans.

The circuit was originally drawn to add manual fan control to a twin-fan BX.

Hope the circuit may be of use.
Cooling fan circuit-001.jpg
Chris
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Huskyxantia
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Posts: 1949
Joined: 30 Jul 2018, 22:11
Location: Surrey Kent sussex border
My Cars: Past cars
Xsara Picasso 2019 to 2022 r.i.p
Xantia mk1&2 1.9D & 2.0Hdi
Peugeot 206 sw 1.4hdi
Other models
Skoda fabia,escort van,ford ka,Vauxhall astra g car & estate, Vauxhall corsa b, Suzuki swift
Escorts mk 1,2,3,4,5 fiestas mk 1,2, Sierra diesel mk1 Mondeo mk1 diesel .
Peugeot 207 , 307sw

Now cars
Picasso 2.0Hdi now gone to scrappie
Citroen zx estate 1.9D the cherished one
Peugeot 206cc raised from the dead & saved from the crusher traded up to a 308cc
307sw traded for the 207 .

Wish list.
Peugeot 405 diesel
106 or 206
Mondeo Mk1 diesel once owned 1.8tdi was real nice.
x 398

Re: Citroen zx radiator fan to manual switching.

Post by Huskyxantia »

Many thanks for this.
Cool , I'll study this later and source parts needed then give it a go , fingers crossed.
Husky. :?
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Huskyxantia
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Posts: 1949
Joined: 30 Jul 2018, 22:11
Location: Surrey Kent sussex border
My Cars: Past cars
Xsara Picasso 2019 to 2022 r.i.p
Xantia mk1&2 1.9D & 2.0Hdi
Peugeot 206 sw 1.4hdi
Other models
Skoda fabia,escort van,ford ka,Vauxhall astra g car & estate, Vauxhall corsa b, Suzuki swift
Escorts mk 1,2,3,4,5 fiestas mk 1,2, Sierra diesel mk1 Mondeo mk1 diesel .
Peugeot 207 , 307sw

Now cars
Picasso 2.0Hdi now gone to scrappie
Citroen zx estate 1.9D the cherished one
Peugeot 206cc raised from the dead & saved from the crusher traded up to a 308cc
307sw traded for the 207 .

Wish list.
Peugeot 405 diesel
106 or 206
Mondeo Mk1 diesel once owned 1.8tdi was real nice.
x 398

Re: Citroen zx radiator fan to manual switching.

Post by Huskyxantia »

So when I find the low and high speed power lines do i splice these to a rocker switch for the manual operation of one or both ?
If that makes sence.
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previously 1989 BX19RD, 1998 ZX 1.9D auto, 2001 Xantia 1.8i auto
and lots of Rovers before that: 1935 Ten, 1947 Sixteen, 1960 P5 3-litre, 1966 P6 2000, 1972 P6 2000TC, and 1975 P6B 3500S
x 1752

Re: Citroen zx radiator fan to manual switching.

Post by white exec »

Locate the Hi and Lo signal lines, and check whether they are +12 or Gnd when fans go into operation.
Splice into those for the manual switch(es).

I don't have a ZX wiring diagram handy, but someone here might well have one.

Caution: don't modify/change the connections to the main relay contacts, as the three relays are inter-connected, and if this is done incorrectly there is a risk of a high-current short circuit.
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Huskyxantia
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Posts: 1949
Joined: 30 Jul 2018, 22:11
Location: Surrey Kent sussex border
My Cars: Past cars
Xsara Picasso 2019 to 2022 r.i.p
Xantia mk1&2 1.9D & 2.0Hdi
Peugeot 206 sw 1.4hdi
Other models
Skoda fabia,escort van,ford ka,Vauxhall astra g car & estate, Vauxhall corsa b, Suzuki swift
Escorts mk 1,2,3,4,5 fiestas mk 1,2, Sierra diesel mk1 Mondeo mk1 diesel .
Peugeot 207 , 307sw

Now cars
Picasso 2.0Hdi now gone to scrappie
Citroen zx estate 1.9D the cherished one
Peugeot 206cc raised from the dead & saved from the crusher traded up to a 308cc
307sw traded for the 207 .

Wish list.
Peugeot 405 diesel
106 or 206
Mondeo Mk1 diesel once owned 1.8tdi was real nice.
x 398

Re: Citroen zx radiator fan to manual switching.

Post by Huskyxantia »

Update,

Things seem to be fine , I unplugged the sensor on the top right side of radiator and bridge the plug and added a toggle switch correct ampage, so far I've only used it 3 times only when idling in traffic cues , watch the needle flick switch if need be.

Today I will plug it back to the sensor and see what happens .... The little saga continues
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Re: Citroen zx radiator fan to manual switching.

Post by Pug_XUD_KeenAmateur »

Have always found it useful to bring the revs up periodically while ticking over, which negates the need for manual fan switching.... about 1200rpm for 10 seconds or so at a time.

If I fail to do this, the recorded temperature stays fairly low, but then shoots up to 95c once I'm back underway, at which point of course the fans come in & get things back to normal.
Puxa
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Huskyxantia
Donor 2023
Posts: 1949
Joined: 30 Jul 2018, 22:11
Location: Surrey Kent sussex border
My Cars: Past cars
Xsara Picasso 2019 to 2022 r.i.p
Xantia mk1&2 1.9D & 2.0Hdi
Peugeot 206 sw 1.4hdi
Other models
Skoda fabia,escort van,ford ka,Vauxhall astra g car & estate, Vauxhall corsa b, Suzuki swift
Escorts mk 1,2,3,4,5 fiestas mk 1,2, Sierra diesel mk1 Mondeo mk1 diesel .
Peugeot 207 , 307sw

Now cars
Picasso 2.0Hdi now gone to scrappie
Citroen zx estate 1.9D the cherished one
Peugeot 206cc raised from the dead & saved from the crusher traded up to a 308cc
307sw traded for the 207 .

Wish list.
Peugeot 405 diesel
106 or 206
Mondeo Mk1 diesel once owned 1.8tdi was real nice.
x 398

Re: Citroen zx radiator fan to manual switching.

Post by Huskyxantia »

Pug_XUD_KeenAmateur wrote: 21 Aug 2019, 13:08 Have always found it useful to bring the revs up periodically while ticking over, which negates the need for manual fan switching.... about 1200rpm for 10 seconds or so at a time.

If I fail to do this, the recorded temperature stays fairly low, but then shoots up to 95c once I'm back underway, at which point of course the fans come in & get things back to normal.
A good idea I've done this a few times even the water pump needs a little kick now and again, and its only 2500 miles old !
Husky. :?
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