Quirky C5 electrics

This is the Forum for all your Citroen Technical Questions, Problems or Advice.

Moderator: RichardW

Post Reply
User avatar
Bandit12
(Donor 2020)
Posts: 394
Joined: 23 Apr 2013, 11:35
Location: Stevenage
My Cars: C5 X7 diesel exclusive
x 12

Quirky C5 electrics

Post by Bandit12 »

I've recently replaced the drivers side heated seat element with a generic replacement as the original didn't work. Job went fine and I was left with 3 wires.
Black to earth-easy just used one of the bolts that secures the seat to the car.
Red with an inbuilt 10amp fuse to a permanent live- piggy backed it of the stereo
REd with yellow trace- Switachable live that went off with the ignition. Used the 12volt auxiliary socket in the centre console next to the handbrake.
Wired it up and its all good:-)
Only one problem, the heated seat button wont switch off which means the 12 volt socket stays live. I double checked by leaving the car locked and looking through the drivers window at the switch every hour.
My question is what can I hook the red/yellow wire up to which is governed by the ignition switch cos I'm concerned I could end up with a flat battery if I leave the car for a few days? Even the cigarette lighter appears to work long after the ignition is off. Car is a factory 2.2 exclusive. Ive removed the inline 10amp fuse in came with to protect the battery.
Any pointers would be helpful

Bandit
2002 Citroen C5 2.2Hdi exclusive estate (sadly gone) :(
2009 Citroën C5 X7 2.0 hdi (136bhp) exclusive estate (Oh wow what an upgrade) 8-)
wheeler
Posts: 6847
Joined: 21 Sep 2002, 19:07
Location: United Kingdom
My Cars:
x 717

Re: Quirky C5 electrics

Post by wheeler »

I don't understand why a heated seat element would need a battery live supply in the first place ? would have thought it just switches on & off with the ignition via its own switch, could you not use the original wiring on the car ?
BX
Posts: 476
Joined: 30 Oct 2009, 00:53
Location: Ireland
My Cars:
x 17

Re: Quirky C5 electrics

Post by BX »

usually not advisable to use the power supplies to the stereo. i made this mistake fitting a parrot kit once. It can cause all sorts of problems including stopping the BSI from going to sleep. On the saloon the aux socket near the handbrake is permanently live and the cigarette lighter socket is ignition switched. The estate might be slightly different. I think that the 12v sockets in the rear of the car may be permanently live.
wheeler
Posts: 6847
Joined: 21 Sep 2002, 19:07
Location: United Kingdom
My Cars:
x 717

Re: Quirky C5 electrics

Post by wheeler »

Would have thought that a heater element might be a bit too current heavy to power off the radio circuit anyway. Personally something like a heater element I would wire from the alternator circuit (via a relay) so that it can only operate with the engine running as I don't imagine it would take long to flatten the battery enough for the car not to start.
User avatar
Bandit12
(Donor 2020)
Posts: 394
Joined: 23 Apr 2013, 11:35
Location: Stevenage
My Cars: C5 X7 diesel exclusive
x 12

Re: Quirky C5 electrics

Post by Bandit12 »

I was concerned about current draw but the new seat element came with an inline fuse which takes a 10amp fuse the same as the stereo. Cant use the original switches etc because the original heated seats are protected by a 30 amp fuse and I was concerned it would cause more problems than it solved. I think the heated seats should switch off with the ignition hence the red/yellow wire. both these live wires feed into a relay. It has a 5 position switch that glows blue all the time there is power to the element but the dial is set to zero. When 1-5 is selected the switch glows red instead.
thanks for the tip regarding the cigarette lighter. I was never happy about using the stereo in the first place but was unsure what was permenant live and what was controlled via the ignition.
I will splice the red wire to the 12 volt auxillary socket and the red/yellow to the cigarette lighter(never use it anyway)

Here is the link to the set I bought

http://www.ebay.co.uk/itm/Pair-of-Carbo ... 0547872127" onclick="window.open(this.href);return false;

Thanks for all the tips guys

Bandit:-)
Bandit
2002 Citroen C5 2.2Hdi exclusive estate (sadly gone) :(
2009 Citroën C5 X7 2.0 hdi (136bhp) exclusive estate (Oh wow what an upgrade) 8-)
wheeler
Posts: 6847
Joined: 21 Sep 2002, 19:07
Location: United Kingdom
My Cars:
x 717

Re: Quirky C5 electrics

Post by wheeler »

Bandit12 wrote:I was concerned about current draw but the new seat element came with an inline fuse which takes a 10amp fuse the same as the stereo. Cant use the original switches etc because the original heated seats are protected by a 30 amp fuse and I was concerned it would cause more problems than it solved.
Remember though the stereo circuit might already be drawing nearly 10 amps, there may be other items on that fuse like interior lights etc & you are adding whatever the heater element draws on top of that.
I cant see a problem using the original wiring as the inline 10 amp fuse will only let it draw 10 amps anyway.
Still dont see why it needs a permanant live, id be tempted to join the battery & ignition lives together & wire them to an ignition feed only.
BX
Posts: 476
Joined: 30 Oct 2009, 00:53
Location: Ireland
My Cars:
x 17

Re: Quirky C5 electrics

Post by BX »

The fact that the original heater had a 30A fuse is not a problem. If you weren't having problems with the original circuit other than a faulty element then I would use that circuit. The inline fuse will give the required protection. There is a lot of mystery out there regarding fuses. The fuse is there to protect the circuit it serves. For reliability car manufacturers often use fuses rated at a multiple of the current drawn by a given circuit. For example there are often two fused circuits for sidelights. The current drawn by both circuits together is usually in the region of a 3.5A to 4A, ie 4 x 5W sidelight bulbs, 2 x 5W number plate lamps, and about 5 x 2W dashboard and switch lamps. However this is usually protected by 2 x 10A or 15A fuses. The important thing is that in the event of a short circuit that the fuse will blow. The only thing we know about most fuses is that they can continuously carry their rated current. To blow the fuse it takes a combination of current and time. For example a particular fuse may be rated to blow within say 5 minutes at 1.5 times its rated current, within 1 minute at twice its rated current and perhaps within 5 seconds at 10 times its rated current. To get this information you need to access the fuse manufacturers data sheets which will have the time * current rupture characteristic graphed. Anyway what this means is that the wiring for the original element should be more than adequate for your new ones. In addition it is probably controlled by the BSI which should ensure that engine running, alternator working and battery being sufficiently charged are all taken into account. If fitting accessories that have never been on the car then I go for the dumb supplies such as the 12V sockets and the cigar lighter.
User avatar
Bandit12
(Donor 2020)
Posts: 394
Joined: 23 Apr 2013, 11:35
Location: Stevenage
My Cars: C5 X7 diesel exclusive
x 12

Re: Quirky C5 electrics

Post by Bandit12 »

Hi guys thank you for all the info. I didn't use original wiring for heated seat because wiring diagrams unclear exactly which wires did what. The seat is fully electric with lots of motors and airbags, n switches etc. I was also unsure if a fault further down the line had caused the original heated element to fail or simply wear and tear. I thought it best to just leave that system alone and tap into an easily accessible auxiliary. I was not happy about using the stereo and never intended it as a permanent fix but just wanted to make sure the heated seat actually worked. I thought that the 12v auxiliary was not permanent live and appreciate the heads up :) I like the idea of following the replacement elements manufacturers instructions guided by you guys. permanent live to the 12v auxiliary socket and the switched 12v live to the cigarette lighter. Ill have a fiddle at the weekend and keep you posted :)

Many thanks again for your input and advice

Bandit :)
2002 Citroen C5 2.2Hdi exclusive estate (sadly gone) :(
2009 Citroën C5 X7 2.0 hdi (136bhp) exclusive estate (Oh wow what an upgrade) 8-)
User avatar
Bandit12
(Donor 2020)
Posts: 394
Joined: 23 Apr 2013, 11:35
Location: Stevenage
My Cars: C5 X7 diesel exclusive
x 12

Re: Quirky C5 electrics

Post by Bandit12 »

SUCCESS! :-D I rewired the seat using the ciggy lighter as a switched 12v supply and the 12v auxiliary socket as the permanent live and it works :-D Switch lights up when ignition is on and goes out when ignition is off.
Many thanks for all the tips spesh how to remove the gear surround to access the lighter socket.

Cheers guys :)
2002 Citroen C5 2.2Hdi exclusive estate (sadly gone) :(
2009 Citroën C5 X7 2.0 hdi (136bhp) exclusive estate (Oh wow what an upgrade) 8-)
Post Reply