paul.h

A bit drastic, I think a new comms unit is £100-200 and only needs programming if you have esp to calibrate the steering angle sensor. I seem to remember from coastline's posts that whilst they all have different part nos. any may do so a good second hand one may sort the problem. If the battery does go flat or is disconnected the date has always needed resetting on my cars so most likely this is nothing to do with a dodgy light switch. Replacement of the comms unit is covered in the Haynes manual although it does not cover the 2.2hdi engine.

I can not really answer the questions but if you do need to depressure the system you do not need to do both the front and the back, only the relevant end. When I had to do some work on mine, once at the right height, I disconnected the battery so the pump would not run and then opened the reservoir cap to release the gas pressure to reduce the amount of oil lost (gas expansion is a greater volume than liquid to lose pressure).

The eurocarparts website may help -shows 3 possibilities. The Citroen car parts site shows many more - maybe you may be able to find a label on the existing one or if you register on service.citroen.com as other professional, citroen owners club, you can see the parts diagrams and use the car's VIN to find the exact one.

I have not seen it on this forum, you could also try the citroenC3owners.com forum. Has the wheel bolts been removed by other than the Citroen dealer or other garage so not possibly been torqued up properly or maybe cross threaded/stripped with an air gun ? - should be 110 Nm (81 lbf.ft) according to the Citroen workshop manual. I would also make sure all the other wheels are on properly, if not already done. If anyone has done any work on my car that involves wheel removal I always check them, usually to make sure they are not on too tight. There were a number of cases of caravan wheels coming loose in recent years and after investigations it was decided the bolts used had to be replaced with stronger ones and torqued up to a higher value - an internet search may find this if you are interested.

2 things you could check, water in the fuel filter to drain out, wear in the accelerator pedal electrics if it does it at the same pedal position each time. There are probably many other things as well and a check of the wiring and sensor connectors around the engine may find something. If you did have a diagnostic check there may be some fault codes logged but ones that are not bad enough to bring on the engine light. If it started on the last fuel tank fill then it may be that.

In the handbook for the C8 (available on service.citroen.com - documentation du bord - then change to English) on the fuses it also mentions the maxi fuses but does not say where they are. You might find these are in the engine fuse box and accessed by lifting the top layer of fuses if it is like the other Citroens that we have had. Possibly one of these has failed. You could also check for 12 volts at the fuses you have already found to see if the problem is before or after the fuses.

It could be anything from a long list of possibilities and the lack of power may be it has gone in to limp mode as a result. Switching the ignition on/off a few times may clear the fault temporarily. Best option is to have the fault codes read and this should point you in the right direction. A fault code reader is cheaper to buy than to pay for a garage to read them for you unless it is part of the fix cost. You could though as a first step look under the bonnet for any loose wiring connectors, air leaks, check if the air mass meter is clean, check the service history for air filter/spark plug, etc replacements - anything that has an effect on the engine performance/efficiency.

When we replaced ours 2 years ago Eurocarparts was the best place for a decent battery.

Best wishes on your recovery. Our C4 also has an awkward battery layout. There is a flap that covers the positive trerminal and this can be used for a positive jump lead and on the ends of the radiator are large bosses that can be used for the negative jump lead - I used these to start a neighbour's car last week. On top of the battery cover are a lot of wires and bolted fuses/links, to remove this lot the positive clamp (coloured black to confuse things) has to be removed, a bolt undone joining a metal wiring link and then these wires can be lifted off with their support. Only then can the battery cover be removed to reveal the battery.

Probably need to check all the fuses, in particular the maxi fuses. We had a Xsara Picasso that once went dead and it turned out to be a maxi fuse. Could have been a weak fuse but once replaced it never happened again. The handbook should show you where they are, sometimes they are hidden in the engine fusebox but I do not know about the C4.

2. I vaguely remember something like this on here where the switch was cleaned and then it worked again - it may have been done by a switch cleaner or taking apart but I can not remember, you may find the post by a search. 3. Our last C5 did this and I never found a fix, it was as if the anti pinch was too sensitive. When winding the window up I used to stop about half way and then use light touches on the switch to close it fully. You could try cleaning the window seals and maybe using something like WD40 on it to see if that helps. If you have a lot of time, maybe resetting the glass in its mechanism could help but I never tried this.

There is a similar recent post (broken handle) on the Problems and Fixes pages and it looks as if they can be interchanged although the parts nos. are different.

This is in the handbook. If you do not have it, it can be seen on the service.citroen.com site, documentation du bord, then shows all vehicles, click on english at the top, then click on the Relay van picture, then select model year, index of sections, changing a bulb. Looks as if there are a couple of nuts inside to remove then pull off the light from the outside and undo some more nuts.

Maybe the front lights are a fault with the light switch which is part of the comms unit behind the steering wheel - a dealer would be able to confirm this. Just to clear up some confusion, high beam and main beam - which of these is the dip beam ? Also could be the relay in the engine fuse box, except it is shared with the main and dip beam lights so if at fault, likely none of these would work. You could unplug the brake switch and put a wire across the connector to see if the rear brake lights come on (the ignition needs to be on for them to work). Then you would know if it was the switch.

The front headlights take separate feeds to each main and to each dip beam from the engine fusebox so hard to guess how this could be connected with the brake lights - worth checking these bulbs have not blown. We have a 2003 1.4 petrol C3 and the bulbs that seem to go a lot are the no. plate and left front dip beam. Is everything else electrical working and all the other lights ? Maybe one last resort could be to disconnect/reconnect the battery in case of a management system error (BSI). If you do, switch off everything, remove the key, open the bonnet and then wait several minutes for everything to shutdown. Then disconnect battery, wait a few mins, reconnect, wait a few mins, put key in ignition, wait a few mins, turn key to first position, wait, turn to light up dash, wait, start engine, reset clock, wind windows down and up to reset anti pinch. Then, if lucky, the problem may have gone.

The Haynes manual for the C3 shows 2 fuses in the glovebox, 20 and 21. One does the high level light and one side and the other does the other light. Your handbook should list the fuses though. Obviously check the bulbs have not blown first. The brake light switch is in the passenger footwell and is the right hand switch on the brake crossover shaft - if at fault, try pushing the plunger to see if the lights then work and if so, it may need adjusting by pulling out the plunger.

You could try for a second hand one in the right colour and then it would be a simple bolt on job - possibly through ebay. I can not imagine a new wing from a Citroen dealer would be more than £100 but the expensive bit is usually painting so maybe the total job could be several £100. To keep the Citroen warranty and bodywork corrosion warranty you may have to go to a Citroen dealer anyway for the repair so still check on this before committing to a repair.

You should get the fault code read (which ought to tell you what is wrong) since the engine management light is on - swapping sensors could cost a lot if you are not lucky and get the right one first time. Referring to your other post, it is possibly not the crankangle sensor since I have read that they do not normally give a management light when faulty but just stop the engine. The circular red dot you refer to, is this the low fuel level one at the left of the fuel gauge and maybe you are on a very low fuel tank level ? If so, a few litres of diesel may help.

According to the Haynes manual, on early 2.0 hdi engines (SOHC), the crankshaft position sensor is on the gearbox bellhousing directly above the flywheel (so next to the engine block) and is held on by 1 bolt.The air cleaner parts may need to be removed to gain access. On later 2.0 hdi engines (DOHC) the sensor is next to the crankshaft pulley at the timing belt end of the engine and held on by 1 bolt - the right wheel arch liner may need to be removed to give access.

You can get cigarette lighter socket plugs/adaptors from car accessory shops and such as ebay (google search on 'car cigarette lighter plug' shows many). Then if you can find an adaptor to go in the lighter socket that will allow your fm transmitter to fit, there is no need for any wiring mods and the car remains as original.

For now, you still have to assume the temp is right due to possible damage if ignored. I would still check if any more air can be bled out, following Haynes, and that the level in the expansion tank is ok. Our C3 was difficult to get the air out, I did not have a header tank when refilling with anti freeze but jacked up the front right corner of the car so the cylinder head and cabin heater bleed screws were at a high point but lower than the water level in the expansion tank to help get the air out. Next suspect the thermostat, usually only a few £ for a new one and they do not last forever, although ones I have replaced before were opening early so the engine did not warm up. If you have the 90 or 110hp 2.0 hdi, the Citroen parts diagrams show a thermostat without the housing, opening at 83°C. Seems to be the mark 2 C5 that is part of the housing. Then it could be the sensor - it is worth checking the wires to it are ok and the connector is clean anyway. If you had a code reader that showed live data, you could see the indicated temps from the sensor and see if they were as expected. Need to beware though if buying one, on diesels not all readers may work until model year 2004. I would also check the water pump is not leaking - there were also on VW cars I think that had plastic impellers that fail, but I do not know about Citroen ones or whether the impeller can become loose. If the head gasket had failed from the first time, there could be coolant loss seen as steam in the exhaust but then the expansion tank level would fall - had this on a petrol car once. On a similar note, on our C3 on 2 occasions a year apart on the same journey (M62) that suddenly went to max temp, nothing obvious was found and later I replaced the anti freeze, thermostat and water pump as part of a timing belt change and it has not happened since. The old thermostat on testing opened at the right temp so may not have been at fault. When it did happen, first time I stopped, second time slowing down and putting the cabin heater on max brought the temp down on the gauge.

Depending on answers to above, the thermostat may need replacing if it is not opening - is the radiator top hose getting hot once the engine has warmed up showing the thermostat is opening ? If the temperature is going high also the radiator fan should be running. If the coolant level is low or the air is not bled out then be careful since if the engine does overheat the cylinder head is at risk of warping. Is the cabin heater working as normal showing circulation of the coolant ? Does the engine run as normal when warming up showing the temp sensor may be ok - these can fail but the other causes of high temp should be checked first due to possible damage if the temp is high. Obviously top up using anti freeze since there is still a risk of freezing weather.

The camshaft sensor is at the timing belt end on top of the cylinder head, could be Citroen part no. 1970 7V, replaced by 1920 QN. The crankshaft flywheel sensor is at the gearbox end of the engine block and to get at it the air filter box and piping may need to be removed, could be Citroen part no. 1920 7N. To check the part nos. are correct, you can look at the parts diagrams on service.citroen.com if you join as a member of the citroen owners club as an other professional. Use the car VIN to get the correct parts. These sensors are under the page mechanical, engine, air fuel supply, Inj calculator sensor. Ideally a diagnostic check of the car would be done since it may be these sensors are not the cause of the fault and I am only guessing. Of the 2, if any are at fault, I would try the crankshaft sensor first.

It could be something like the crank position sensor, when these are failing they are ok when cold but on warming up give a fault that would stop the engine but would not give an engine mangement fault code. Then after it has cooled down it would allow the engine to start again.

For the wiring diagrams you have to load the SVG viewer which comes with it, if not already done. There should be some info in the help pages that can be found from Start, All Programs, SEDREAC, Help but from memory I think it is in the left column of the wiring pages. If printing I find using the mouse right click and print preview easiest.