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
Citroen zx radiator fan to manual switching.
Moderator: RichardW
-
- Donor 2023
- Posts: 2056
- Joined: 30 Jul 2018, 22:11
- x 429
-
- Moderating Team
- Posts: 7445
- Joined: 21 Dec 2015, 12:46
- x 1752
Re: Citroen zx radiator fan to manual switching.
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.
* 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.
Chris
-
- Donor 2023
- Posts: 2056
- Joined: 30 Jul 2018, 22:11
- x 429
Re: Citroen zx radiator fan to manual switching.
Many thanks for this.
Cool , I'll study this later and source parts needed then give it a go , fingers crossed.
Cool , I'll study this later and source parts needed then give it a go , fingers crossed.
Husky.
-
- Donor 2023
- Posts: 2056
- Joined: 30 Jul 2018, 22:11
- x 429
Re: Citroen zx radiator fan to manual switching.
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.
If that makes sence.
Husky.
-
- Moderating Team
- Posts: 7445
- Joined: 21 Dec 2015, 12:46
- x 1752
Re: Citroen zx radiator fan to manual switching.
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.
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.
Chris
-
- Donor 2023
- Posts: 2056
- Joined: 30 Jul 2018, 22:11
- x 429
Re: Citroen zx radiator fan to manual switching.
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
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
Husky.
-
- (Donor 2018)
- Posts: 1168
- Joined: 22 Apr 2013, 17:24
- x 232
Re: Citroen zx radiator fan to manual switching.
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.
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
-
- Donor 2023
- Posts: 2056
- Joined: 30 Jul 2018, 22:11
- x 429
Re: Citroen zx radiator fan to manual switching.
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 !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.
Husky.