159 2.4 20007 plate
19,500 DPF/EGR by
AO Silver Member
Join Date: May 2009
Location: United Kingdom
Either take it to a good independent or as r11co says get a free copy of FiatECUScan and either a 327ELM lead or a KKL lead and read the fault code.
The FiatECUScan site is very confusing with what leads are needed, there has got to be an easier way to identify what you need - just buy a single KKL or 327 and, for connecting to the engine ECU, you do not need any adaptors nor do you need to mess about with modifying pin connections.
You may find that the software fails to connect. If the car has never been on a computer reader the connections can get a bit dirty and the solution is to plug the socket in and take it out a few times, that is usually enough to clean the pins and get a connection between the car and computer.
The software will read the fault code and probably let you reset it and turn the light off. Though if there is a permanent fault on the car the code and light will quickly re-appear. Once you know what the fault is the first thing to try is just disconnecting and reconnecting at the sensors plug connection. Many "faults" are just the connectors getting a little corrosion and going high resistance. Unplugging the connection and putting it back can sometimes fix the fault and save quite a lot of money.
Finally, a voltmeter is a very basic test of battery condition. To test it properly you must put the battery under load and see how well it holds it voltage and for how long. To do that properly you need a load or "drop" tester for that. Take the car to a battery supplier and they will test the battery for you.
Last edited by kandlbarrett; 29-12-11 at 11:30.