C4 Coupe Won't Start

[Ozzy's mum]

Please, if anyone can help me!

My citroen C4 coupe (diesel) started fine this morning.  My husband drove for 40 miles, stopped the engine. When he got back in the car, he put the key in the ignition and turned it to pre-ignition.  He then received a phone call so didn't start the engine, and now nothing at all is working, no electrics, nothing.  A local garage has put a booster on the battery but that hasn't made any difference. Any advice would be hugely appreciated as he's now stuck in the middle of nowhere.  Many thanks in advance.

[paul.h]

Welcome to the forum.

 

If nothing happens when the key is turned and there are no warning messages and the dash is not lighting up, then most likely a fuse has failed. There are fuses in the glovebox and under the bonnet. As well as the normal fuses there will be maxi fuses hidden in the engine fusebox and there are fused links on top of the battery.

 

If it is a fuse failure then most likely it will be one of the maxi fuses. The Haynes manual for the C4 lists them as

 

MF1 30/50 amp engine cooling fan

MF2 30 amp ABS/ESP pump supply

MF3 50 amp ABS/ESP control unit

MF4 and MF5 both 80 amp built in systems interface (BSI)

MF6 80 amp passenger compartment fusebox

MF7 20 amp diagnostic connector/additive pump

MF8 spare

[paul.h]

To get to the maxi fuses in the engine fuse box, first disconnect the battery, remove the engine fuse box lid, unclip the 4 wiring connectors on top of the fuses, undo the bolt fastening the battery cable to the fuse box then pull up the fuse holder. The maxi fuses should now be seen. When reconnecting the battery do not be too quick to start the car since the bsi needs a bit of time to reset. I have found the following procedure in the C4 Technical section Common Problems pinned topic works:

 

11. Odd electrical problems caused by wrong battery disconnection procedure.

If you need to disconnect the battery and not do a BSI reset procedure, I have found the following has not given me any problems on a 2004 and 2007 C5 and a 2003 C3:

- remove the ignition key from the car

- open the bonnet

- wait a few minutes for the BSI to shut down

- disconnect the battery negative terminal

 

When reconnecting

- ignition key out of the car

- reconnect the battery

- wait a few minutes

- insert the key in the ignition and wait a minute

- turn the key to the first position and wait a minute

- turn the key so the dash lights come on and wait a minute

- start the engine

- take the windows down and up to reset the anti pinch

- reset the clock (and radio on the C3).

[Ozzy's mum]

Hello, thank you  for the replies.  There is a message coming up showing it as being in economy mode, but I thought that was a temporary problem?  Otherwise, nothing else electrical is working. 

If I disconnect the battery will I need to re-program the ignition key? It's a '56 plate Coupe.

[Ozzy's mum]

Have checked the fuses, nothing wrong there. Dashboard lights and 'economy mode' warning come on, but radio, wipers. lights etc not working. Have spoken to a couple of Citroen garages but no-one seems to know what the fault could be.

[paul.h]

Economy mode is a Citroen/Peugeot thing to prevent the battery going flat. If the radio or inside lights or doors are kept open after the engine is stopped, economy mode cuts in to switch off things like the radio and inside lights. Once the engine is run again it will reset and these things will work again. This is normal and will not prevent the car starting.

 

Disconnecting the battery will not require the key to be reprogammed.

 

Do the headlights/sidelights/hazard lights/central locking work ? When you turn the ignition key is there any noise from the starter motor such as a clicking sound as the solenoid moves ?

 

Did you check the maxi fuses ?

 

I suspect if you ring up a garage they will not suggest anything other than to bring the car in for a check since they will be afraid of giving a wrong diagnosis and being liable for consequences.

[Ozzy's mum]

Hello,

The hazard warning lights and headlights are working, as is the central locking. When the key is turned there is a clicking sound, and yes, the maxi fuses are ok. When the key is turned to pre-ignition, all the dashboard lights come on and then go off as normal. The problem is, our local Citroen garage can't do anything until the middle of next week, so we're stuck without a car in an area where public transport is a myth! 

[paul.h]

Diagnosing something from a distance is not easy but it could be the starter motor or its wiring have failed or become disconnected. If the battery voltage is low though it may not have enough power to run the starter motor. So first checks would be the battery voltage which should be about 12.5 volts when the engine is not running, then check the wiring to the starter motor and for a 12 volt supply at all the starter motor connections when the ignition switch is turned. If these things are all ok and the starter motor is not turning then possibly the starter motor needs replacing. For such a fault you would not need to use a Citroen dealer.