Hi, just fitted a new stereo to my daughters punto yesterday, needed a switched live as the original audio connection didn't have one so took a feed from the cig lighter. This morning the car would turn over but not start, the fuel guage was showing empty but there was plenty of fuel in the tank. took the stereo out again but the problem persisted. Finally gave up and called the AA. The guy came and checked all the fuses and initially said it was an immobiliser prob. He kept checking and eventually took the dash off, the car started first turn of the key. He refitted the dash and the car would start but the rev counter, fuel guage and temp guage didn't work and the clock kept resetting to midnight, checked a few more fuses and relays and then the car would start with revs but stop as soon as the revs dropped. Checked a few more things and then the car would start and remain running without the rev counter or fuel and temp guages, and thats how it remains at the mo. Did take it for a quick drive to see if the speedo works..........no...
Any ideas as to what might be the prob

yes i think i do
its something i keep warning about but nobody seems to listen
i believe you may have put a voltage back into the bsi where it shouldnt go and its damaged it
needs more delving obviously make sure no wires have burnt through too seeing as moving things gets something going

sorry would need the car to help further so put it over to anyone else

Have another look at fuse 37 and 53 just to make sure there not blown as these control dash/time, 37 is engine running, 53 is on battery power, both 10A

also maxi fuse f02 is dashboard functions, worth checking that too

have you connected the radio to the Can-Bus system? it sounds like you might have done

the Punto doesn't use an ignition live on the standard radio because the Can-Bus system (which is the computer network all the systems in the car use to communicate with each other) sends a signal to tell the standard radio if the engine is running or not. unless you remove the can-bus wiring completely from the radio (ISO) connector you can end up connecting the can-bus system to ground, live or anything else.

Genius idea using the Cig lighter as a switched live but i would like to know more about how you have connected it and the rest of the radio as removing the radio didn't solve the problem i can only conclude the connection is still somehow in place,

worst case scenario you may have caused damage to the can-bus system

I didn't alter any of the other wiring as the iso connector for the audio had no wire for the new stereo switched live position. I just took a wire from an old iso block and connected it to the switched live on the cig lighter and put it in the audio iso connector and the stereo worked

so you connected to pin 7 i suspect with no other alterations means...

that pins 1 and 3 are still connected to the aftermarket radio. on the punto's ISO connector these are for the Can-Bus system when fitting an aftermarket radio these need to be disconnected to prevent damage to the system, they normally provide speed information and reverse engaged on fancy aftermarket units but because they are used so infrequently fiat used them for the Can-bus.

when fitting a radio to a Punto most people use an adaptor bought from halfords for £10 this detaches the can-bus completely avoiding any issues. try fixing the problems with the radio first or remove it completely, disconnect the car battery for a few hours, then reconnect the battery and see if the fault still remains.
sadly though there is a good chance you've caused some damage to the Can-bus for which you will need S and B's often excellent advice to remedy

Many thanks for the advice, the car did originally have a non standard stereo (with broken cd player)fitted when my daughter bought the car and I assumed that all that was needed was a switched live.
Any ideas as to the worst case scenario

Update...the car has been to fiat DEAleR-ship for a week and they say they have traced the fault to a missing wire on the computer ??? They say the problem is the clocks and that it needs a new set of clocks. Originally quoted approx £240 but now they are stating that the clocks are quite unique and the actual price is £333.17 + vat. Just thinking they are on a rip off as the car is a standard 1.2 8v. Has anyone else heard of these unique clocks???

Damn those magically disappearing wires that for the last 8 years have sat happily in place doing their job then without warning or reason disappear never to be seen again.

sadly the pricing problem could be one of their mistake, given this is the change over year they could have quoted originally for a slightly different model i,e one with/without a rev counter or changes between the mk2 2003 and the mk2b 2003 punto which may account for the difference in price, to cover their own arses and mistake they are claiming that the part is unique and they didn't realize. this doesn't get away from the fact that it most probably still requires the more expensive bit to fix the fault

i wouldn't be happy with their 'missing wire' explanation get them to show you the so called missing wire and explain how it has come to be missing? £300+ is a lot of money to fork out on what is essentially a pretty crappy explanation of the problem.

Look on ebay for a digtal dash plenty of them easy to fit cheaper than main dealer