C4 Jbl Problem, Or Something Else.

[pete the elder]

I have a C4 2 Litre HDI auto.It was factory fitted with a JBL sat-nav system.On this unit there is a little red light just above the S.O.S. Citroen assist button but no mention of this light in the book that came with the car/radio.

Now for the problem.Most mornings when I start the car the red light comes on,the radio will not work the sat-nav screen stays blank and the front and rear parking sensors don't work.Everything else works.If I then drive off and run for 15 minutes or so the little red light goes out and sat-nav and radio ect. all start working .

My first thought was that the system was sensing low battery voltage since the book says that if the engine is not running and you use the radio it will go into a power saving mode and switch the radio off after a period of time in order to preserve the battery.

I have checked the battery before switching on and it reads 12.5-12.6 volts .Fully charged battery voltages are normally 12.6-13.2 volts,so I can't think low voltage is the problem.When the engine is just ticking over the alternator is charging at 13.2V.

I am loath to go to a garage for an answer since I know what the answer will be,"open your wallet and repeat after me,Help yourself."

Any ideas please,thanks for reading this far.

Pete.

[qman3428]

Dont know for sure as mine doesnt have Sat nav but it could be searching for GPS

[pete the elder]

Dont know for sure as mine doesnt have Sat nav but it could be searching for GPS

 

I suppose it's a possibility but not sure why it would shut down the the radio and front and rear parking sensors as well.

Thanks for the thought though.

Pete

[pete the elder]

The other things that don't work that I forgot to mention,I also loose the telephone and the speedo changes from miles to kilometers.

Any vehicle electricians on here with a clue?

Pete.

[pete the elder]

Right,it's pinned down to the Navi-Drive system definitely.If I keep doing a system reset by holding the dark button down it all starts working OK.I can hear the disk in the Navi-Drive spinning but can't locate the actual unit .Sounds like it's coming from the area of the glove box but I can't see the unit.Anyone know how to get to it?I'm hoping that a disk or laser clean-up will solve my problem.

Pete.

[paul.h]

Not sure if I can help but a few comments.

- A fully charged battery is supposed to be 12.7 volts and 12.5 or less is discharged.

- With the engine running I have always seen 14 volts measured across the battery so if you are only getting 13.2 volts then that is low - is the drive belt slipping/in need of replacement or the battery terminals/an earth point not making a good connection or your volt meter is not accurate ?

- All the Citroens we have had go into eco mode (battery saving mode) if the engine is not running and something is using the battery such as internal lights/the radio and after about 15 minutes these are shut off. To reset this the engine needs to be started. Something worth a try may be to disconnect the battery for a while to reset everything.

- Our C5 has a navi drive and I think the disc is a hard drive built into the radio unit but it is always spinning by the sound of it when switched on/the engine is running/if a door is opened. The handbook with the car does not mention the red light above the SOS button either.

[pete the elder]

Not sure if I can help but a few comments.

- A fully charged battery is supposed to be 12.7 volts and 12.5 or less is discharged.

- With the engine running I have always seen 14 volts measured across the battery so if you are only getting 13.2 volts then that is low - is the drive belt slipping/in need of replacement or the battery terminals/an earth point not making a good connection or your volt meter is not accurate ?

- All the Citroens we have had go into eco mode (battery saving mode) if the engine is not running and something is using the battery such as internal lights/the radio and after about 15 minutes these are shut off. To reset this the engine needs to be started. Something worth a try may be to disconnect the battery for a while to reset everything.

- Our C5 has a navi drive and I think the disc is a hard drive built into the radio unit but it is always spinning by the sound of it when switched on/the engine is running/if a door is opened. The handbook with the car does not mention the red light above the SOS button either.

 

Thanks Paul,

After my first post I did spend some more time checking the battery.I fully charged it ,left it overnight and checked it the next morning.It had gone down to 11.8V. I replaced the battery with a new one and the alternator now charges at 14.2V when idling.

The Navi-Drive still gives problems on start-up until I do a reset using the "Dark" button,so I now feel sure that the problem is in the unit itself. All I need to do now is to find out how to get to it.

Thanks again, Pete.

[paul.h]

I have looked at a Citroen workshop manual (previous years copies can be bought on dvd from such as ebay since a Haynes is not available and then it would not have this detail. There is a French ETAI manual for the C4 but only covers the 1.6 engines). There is a long list of possible fault codes for the radio unit which would need such as a Lexia to read them. Many of them say the transverse warning lamp will flash orange for 3 minutes but do not show where this is but it may be the red one you are seeing. It looks as if it may be a fault with the radio unit or its wiring but without the codes it is not possible to tell. However, it may be worthwhile pulling the radio out (2 U shaped clips pushed in the holes at each end should release it although our C5 needs a torx bit) and checking the connectors at the back are not loose. If you do this without disconnecting the battery you should be able to check if you can hear the hard disc in the unit spinning to confirm its location. If you replace the radio the new one will most likely need coding to your car. If you do disconnect the radio, first disconnect the battery to avoid any problems with the car ecu.

[pete the elder]

Thanks Paul, that is really helpful,especially the radio removal info.It can't do any harm to jiggle the connectors and may just solve my problem.

Pete.

[pete the elder]

Final episode.After diagnostic checks and new software a new unit was fitted by the dealer.My original cost estimate turned out to be correct,an arm and two legs!

The lesson I have learned is that I will never ever purchase another car with an integrated Sat-Nav system.When the system went down I lost Radio,Telephone,Parking Sensors and an MPH speedo in addition to the Sat-Nav .

In future it's a stand alone Sat-Nav for me. I could have bought 6 or 7 top range units for what the repair cost.

Pete.