post a picture of the fuse and the pages from your owners manual. Lets see if we can spot anything.

of some else could post there fuses from a 100hp might speed things up.


if its the same as the 1.2 its just a matter of swapping relays to see if the fault changes as they are the same size.

but let's get back to cranking and no error before we introduce another variable.

is this the car with the blower fault ?

This car does not have the blower problem. That's been put back to how it was. Heater fan works on speeds 3 and 4 only.

This is the 100HP previously all working fine. It's had a new set of spark coils and a USB socket in place of the ciggy lighter. That is disconnected in case it was the problem. No signs of over-heated wires. Every single fuse way (with contacts) in all three fuse boxes has a good fuse.


Ive just been through all of the fuses one-by-one every one of them is good. They are all seated properly.

I have also checked every relay in engine bay fuse box with a 9V battery and ohm-meter. All are switching and all make good contact.

Could this possibly be an ignition switch problem? Is it known for some contacts to fail so that MER position leaves the body computer powerless?

Did this problem start when you removed from lights and fuse box?

Is there more to the "fuse box" than fuses?

Maybe reassemble every thing you removed ?

DaveMcT said:

Could this possibly be an ignition switch problem? Is it known for some contacts to fail so that MER position leaves the body computer powerless?

Click to expand...

Not that Im aware..

Worth unlocking the rake adjuster and running through some full arcs though..

jackwhoo said:

Did this problem start when you removed from lights and fuse box?

Is there more to the "fuse box" than fuses?

Maybe reassemble every thing you removed ?

Click to expand...

For exactly this reason, I have not messed with the OEM fuse box not touched any of them or any OEM wiring.

I have added a new four way fuse box to power the new lights but job stopped when engine would not start. There is no connection to existing wiring

I have pulled up a couple of ignition switch threads that sound a bit familiar. They make me suspicious of the ignition switch. Any thoughts?

https://www.fiatforum.com/lets-talk-fiat/342257-panda-ignition-problem.html?342257=#post3403608

https://www.fiatforum.com/panda/438...sh-lights-other-woes.html?438479=#post4168857

Maybe switch but I can't see how it could be powering up the engine ecu (proof mil lamp coming on ) but failing to power up other ecus etc.

Does rev counter needle move at all while cranking on starter?

Any luck connecting mes?

What have you taken off in preparation of fitting additional front lights?

Did you disturb any of the smaller wires on the positive battery terminal?

MrMagoo said:

Did you disturb any of the smaller wires on the positive battery terminal?

Click to expand...

Mine has one thick red lead from the battery to the fuse box and another thick red lead to the starter and alternator. There are two M6 studs on the top. I have used one to take power to the new fuse box. The earth side has more leads but I've not yet reach the earth side of the ligthing cuircuit

jackwhoo said:

Maybe switch but I can't see how it could be powering up the engine ecu (proof mil lamp coming on ) but failing to power up other ecus etc.

Click to expand...

I know, it's all very odd (see below). BUT others had strange starting problems so I'm suspicious of lose connection at the ignition switch or the MAR contacts are not all connecting. Not having a wiring diagram is a nightmare.

jackwhoo said:

Does rev counter needle move at all while cranking on starter?

Click to expand...

I have just been out to check and IT STARTED !!! as if everything was always fine and dandy!!!

jackwhoo said:

Any luck connecting MES?

Click to expand...

Now its chosen to start we will have to see. Too late now.

jackwhoo said:

What have you taken off in preparation of fitting additional front lights?

Click to expand...

The front bumper was removed and painted to match the car (original damaged by deer impact last year). Took the chance to replace the spot lights with LEDs.

The centre console around handbrake has been taken out to fit switches. I have made a new aluminium plate to carry a three way toggle switch. Fully separate four way fuse box mounted on inner wing with power from a spare M6 thread on the battery lead. The lights have long leads ready to connect. Wiring to the light switches etc is still to be run and connected.

Grey covers removed at base of driver's side A pillar and sill to check for earths (none found). Rear seat removed to test fuel pump.

Nothing touched under the bonnet. Nothing touched under the steering wheel.

'It Started'..

1st time you have heard the tank pump run in days..??

I replaced the stick coils last year because it was intermittently reluctant to start and would sometime run rough for a few seconds. The new coils helped but not as much as expected and fuel consumption stayed much the same.

I'm beginning to wonder if this event is connected (or not ). I will have to get the steering column covers off to have a look at the wires and ignition switch as that's the only thing I can think of that could cause such an odd fault.

varesecrazy said:

'It Started'..

1st time you have heard the tank pump run in days..??

Click to expand...

Five days ago it started and ran fine. I warmed it up and switched off as it had not run for a month.

The following day it refused to start, which is when I created this thread. Until tonight it has refused to start at all. Engine cranked but nothing else happened.

2 days ago, I pulled out the rear seat to test the fuel pump. Checked for voltage pulse at ignition on MAR. There was none.

Created a jump wire from battery to run the fuel pump independently. Engine would not start even though there was pressure in the fuel rail.

Tonight it started but I wasn't listening for fuel pump so no idea if it primed at MAR. It's obviously working as the engine ran normally.


The LCD screen is still showing ABS and steering errors. Hopefully the MES can help with that tomorrow.

All dash warning lights (immob, charge, ecu, etc) behaved as normal.

Happy days. You could be right if this is connected to the coils. Filler her up with V-Power petrol. I had a few issues with my 100hp. New coil packs and spark plugs. Wouldn't start.

It had been sitting for about a year. Long story short. Fresh fuel in the tank and a few sprays of "Start you Bastard" brought her back to life and purring. Probably completely different to your problems.

Glad to hear that's she's started ?

I've been following this thread with interest. I haven't posted before because you guys were all making sensible suggestions and doing all the right things.

This incident crystallises most of the reasons why I worry about being able to continue to maintain a modern car as it ages. A plethora of sealed boxes containing proprietary and undocumented electronics, hooked together by a set of cables and connectors which have been 'value engineered' to the bone, the whole lot being just about fit for the purpose of getting the car through the warranty period.

The new car market is driven by folks whose look only at 'fashionability' and the size of the monthly payment - maintaining the car in later life just isn't part of the purchasing decision. Manufacturers want to sell new product; they've no interest in keeping ten year old cars on the road. Franchised dealers want routine work that can be done by relatively unskilled staff; they don't want complex problems that need ever harder to find skilled technicians to diagnose and fix.

Forums like this one help those of us with a bit of technical savvy to fight back.

Dave, if anyone can get to the bottom of this, it's you. Normally you'd be the one making useful posts at a time like this. If you can't work it out with the car in front of you, there's no way I'm going to be able to work it out sitting at a keyboard.

I have other things to do today so the final analysis will be a while. That said I think the ignition key thread -
https://www.fiatforum.com/panda/438...sh-lights-other-woes.html?438479=#post4168857 offers some clues as that OP had strange warnings on the dash.

JR is spot on about cars today. They are built to suit the factory, but senior management don't want to make investment in system that helps the factory or the end user. That's why we have tangles of wires under fuse boxes, computers rammed up under the dash with fuses you can only remove with miniature pliers and yet more stuff that degrades because the parts are unsupported.

I've been watching Sandy Munro stripping down Tesla cars. They are not perfect (of course) but its clear they are innovating to make production easier and more reliable. Big Auto's refusal to solve the stuff that costs them money AND the end users money will bite them. We are likely to end up with one brand car industry.

My Panda is of course 13 years old and we know things should have improved since then. However the commonality of parts (especially electrical) with modern models shows the factory is refusing to develop it's designs. Let's assume my problem is the ignition switch, who would bet against the components from today's 500 and Panda or even every other Fiat being the exact same as my 2007 Panda.

Monro said that wiring is a huge expense at the factory because they can't get robots to build or install the looms and clip together connectors. It's all "mandraulic" costing money and adding unreliability. The best part is no part at all, but Fiat seem to have made it ever more complex with money "saved" on cheap switches and connectors.

KungFooPanda said:

Happy days. You could be right if this is connected to the coils. Filler her up with V-Power petrol. I had a few issues with my 100hp. New coil packs and spark plugs. Wouldn't start.

It had been sitting for about a year. Long story short. Fresh fuel in the tank and a few sprays of "Start you Bastard" brought her back to life and purring. Probably completely different to your problems.

Glad to hear that's she's started ��

Click to expand...

I have not touched the coils since fitting a new set last year and always use posh petrol. I have not touched anything engine related, Felt it best to leave well alone rather than open another can of worms (or two).

She's started but the fault is still there ready to bite me in the arse. Probably somewhere near Stonehenge at 10pm on a Sunday.

DaveMcT said:

I have not touched the coils since fitting a new set last year and always use posh petrol. I have not touched anything engine related, Felt it best to leave well alone rather than open another can of worms (or two).

She's started but the fault is still there ready to bite me in the arse. Probably somewhere near Stonehenge at 10pm on a Sunday.

Click to expand...

Just make sure you have breakdown cover, just in case. That reminds me- mine is due, RAC have increased the renewal by 58 quid! Didn't use it once last year either ?

DaveMcT said:

I have not touched the coils since fitting a new set last year and always use posh petrol. I have not touched anything engine related, Felt it best to leave well alone rather than open another can of worms (or two).

She's started but the fault is still there ready to bite me in the arse. Probably somewhere near Stonehenge at 10pm on a Sunday.

Click to expand...

Were you powering the pump direct from the battery by back probing the pump plug with the loom still connected to rest of car?

When it started had the battery direct to pump wire been removed?

I proved the fuel pump with wiring loom unplugged. It worked with the direct wire proving the pump is ok. Once done plugged the wiring loom connector back to the pump.

The surprise start happened with everything connected as it should be. Now need to find what looks like an intermittent fault.

DaveMcT said:

I proved the fuel pump with wiring loom unplugged. It worked with the direct wire proving the pump is ok. Once done plugged the wiring loom connector back to the pump.

The surprise start happened with everything connected as it should be. Now need to find what looks like an intermittent fault.

Click to expand...

At the risk of being overly simplistic, a loosely fitting &/or corroded fuel pump connector? Removing and replacing it might just have been enough to get the current flowing again.

I've lost track of the number of computers I've 'fixed' by powering down, taking the cards out of their slots & replacing them.