355 Electrical issue car shutting down, fault possibly found?

Thank you @Qavion , very helpful as always.


The blue cable is powered with the key on, and no power with key off.


I replaced the P relay which relates to some ignition circuits, I found the fuse box was quite oily in places, almost like vasaline


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The “Vaseline” may be dielectric grease, such as “DC4 compound”. It’s to keep moisture from electric circuits, but it’s a very good insulator. In some cases, it can make things worse. If, for example, the grease is put on loose relay pins, it can make contact even worse.

So are you saying relay P fixed the issue?

 

No I just replaced the relay as I had a new one lying around, doesn’t seem to have helped

 

I didn't think it would. Relay P only affects the windscreen wiper, brake lights and the radiator fans.

 

I was looking for a place to put a switch if only the 2 blue wires were affected on the ignition key connector, but went down a bit of a rabbit hole. Both blue wires go to the back of the relay panel. Actually, if you wanted to check that the key was providing power to the relay panel, you could pull relay "P" and check the relay socket pins which correspond to the relay coil (for 12 volts) with the key on. i.e. put the voltmeter on relay socket pin 85 (or maybe 86) and a good ground and turn on the key.

Note that the 348 wiring diagrams show two blue wires coming from the ignition key connector to the relay panel, but someone reported that there was only one wire on the actual car. I'm wondering if the 355 is the same.

 

I'm wondering if the radio installer cut into one of the the blue wires on the ignition key connector and spliced the "blue cable" into that. Maybe the splice is failing?

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According to the wiring diagrams (5.2), the ignition key blue wires go to these pins on the back of the relay panel:
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Ignore the circled wires. There is a blue/red wire on pin 8 of plug "A" and there should be a blue wire on pin 8 of plug "C", but I'm not sure if I can see the latter in the photo. These wires provide redundant paths between the key and the relay panel. If there is only one wire, you could perhaps splice in your emergency switch to the red/blue wire and perhaps the battery bus bar behind the relay panel. See the red "+"

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It won't be an easy process. It may be easier just to find your fault. I would be looking for a splice near that ignition key plug or somewhere closer to the relay panel in the footwell. Unfortunately, it looks like your blue cable is a similar colour to OEM wiring, so it may be difficult to spot an aftermarket splice.

At least you know the ignition key itself is ok.

 

@Qavion

thanks very much indeed for the above.



on the first page, you asked me to check fuse 24 (AC) for power with the key on when the issue presented itself, and also fuses 25 and 26.

I have performed two tests as the car right this moment has the issue, key on and no power, unless I connect the stereo amp leads which then powers up the car.

test 1 is key on
Test 2 is key on with amp leads connected

Please note I have 3 fuses which are shown as blanks in the diagram , I have 2 in between 29 and 30 (which I have called 29.5 and 30.5. And I also have one in between 22 and 23 which I have called 23.5

Fuses which have power

test 1


19
27
28
29
30.5
30
31

test 2

19
24
25
26
27
28
29
30.5
30
31

so the fuses you mentioned, 24,25 & 26 have no power when the issue appears, if I connect those amp leads they then recieve power

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Ill check tommorow, we go on holiday/vacation Tuesday so will be a couple of weeks until i can do a deep dive into things.

thanks again, without this help I’d be screwed!

 

Sorry, I deleted my previous message. I thought I saw an error in my logic. I should be able to sort it out by tomorrow.

 

LOL.. wished I hadn't deleted my message. I was right the first time...

Anyway, check for two blue wires on the steering column connector (lower half). See graphic below:

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As mentioned in my deleted message, you won't need to take the shroud off the steering column to see this plug.

If you have time and the problem is still there, check for key power going to the coils of relays P (E12), Q (E7), R (E11), O (E9) and L (E10). Sorry, don't know if that's pin 85 or 86. Check 85 first.

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The "E" numbers are printed on the relay panel.



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If possible and if the issue is not present, would you still let me know which pins (85 or 86?) of those 5 relays have power with the key on?

It's really weird that the problem is coming and going. I'm not sure what would cause this if the car is not being moved. Also, I'm still not sure if the problem is a splice in the wiring between the key and the relay panel or if there is an internal relay panel issue. Your tests and observations should help clear this up.

 

Disregard my last message. There has to be something I'm missing here.

I just checked the wiring on my F355 5.2 and there are two blue wires on the steering column plug, so I'm sure yours has. This means that the fuses and relay coils have two ways of getting power. E.g. fuse 24 has two ways of getting power:

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If you are sometimes not getting power to fuse 24, then it would suggest that you have two wiring problems. On a car without that radio wiring modification, normally you would suspect that the ignition switch itself was faulty (i.e. a single fault). But, since you are getting power on the blue radio wire with the key on, this suggests that your ignition switch is ok.

There is a possible solution to this.... It could be that your ignition switch is so intermittent that, when you did do the check on the blue radio wire, the ignition switch was working again. I would carry out a continuity check on your ignition switch and repeatedly turn the key on and off:

Turn off your battery using the forward luggage compartment switch and disconnect the steering column plug. Then, on the key side of the plug, put an ohmmeter between the red wire and the light blue wire. i.e. not the light blue wire with the black stripe on it. Then turn the key on and off several times, wiggling the key. If you do find an intermittent continuity fault, then try checking for continuity between the red wire and the light blue wire with the black stripe on it. You can also check for continuity between the red wire and the white wire in the START position. Use the diagram above as a reference. R = red. A = light blue. A|N = light blue with black stripe. B = white.

Note that when I said the lower half of the steering plug in my previous message, I meant the car side of the plug, not the ignition switch side of the plug. However, looking at my connector, the plug is horizontal or perhaps a little upside down.

This is a 550, but the wire colours are similar:

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If it's the ignition switch that is faulty, then it could be expensive issue. Some folks have used parts of a Fiat ignition switch as a solution, but due to the differences between a Fiat and Ferrari switch, there was no power in the ACCY position. Rewiring may be involved if a Fiat switch is used.

 

There seems to be some second hand ignition keys online, but some are the 6 pin Euro type, some don't have keys and others appear to be in poor condition.

 

When the issue was present, did you do a voltage check on the radio blue wire without turning off the key? Or did you turn off the key, turn it back on again, then check the voltage?

Maybe Miro @m.stojanovic can see if I'm missing something here:

Summary:

1. Intermittent key power to relay panel.
2. Wiring diagrams show two power paths from the key to the fuses and relay coils. This is also shown in the 348 diagrams, but some cars don't have a second wire.
3. Shorting the radio's key power and live battery power wires appears to fix the issue.
4. Unsure of how the radio is wired in. I assume it's only wired into one of the blue wires coming from the key. Of course, there are key power wires all over the car. It could be tapped in anywhere.

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1. Splice 30045 goes to:
2. Roof warning buzzer on Spider
3. Steering column light switch for sidelight and headlight control.
4. Seatbelt/Door Warning Module on USA cars.

Perhaps this can be used to diagnose the issue.... although that might only be of use when we get to the stage of pulling plugs off the back of the relay panel or cutting into the wiring.

@Ben111 Don't leave those two radio wires shorted together and go on holidays. If they are bypassing the ignition switch, you will have a truly flat battery by the time you get back.

 

@Qavion

Just on my way out to work, but to clarify since I made the thread after those 3 breakdowns the car hasn’t moved, and the issue is intermittently presenting itself still.

here is the pattern since I parked the car.

-broke down 3 times on the Saturday, 3rd time go towed home

- Sunday morning the car is fine again

- removed battery, main ECU and stereo amp for 2 weeks

- reinstalled the battery and ECU, left amp removed, Issue is PRESENT, accidentally touch the two amp leads and find it fixes issue

-the next morning the car is fine again regardless of the amp leads

- yesterday I tried the and the ignition was fine on its own initially, but I turned the key on and off 3 times and the fault came again, connecting the amp leads rectified the issue


Whatever the issue is, is now at a point where it appears to be occurring more often

 

Not sure what the missing word is, but I just need to know if you switched off the key again before shorting the amp leads. Any movement of the key may fix or break the ignition circuit. If it's broken leave the key on and then short the leads. You may have already done this, but I have to be sure.

From a faultfinding perspective, this would help. I hate working with intermittent faults.

 

If you do this and the car works, then we are back to your car having two faults... or perhaps the internals of the relay panel are not as shown in the wiring diagrams.

Some easy tests if you lose power and the key is on (Don't short the amp wires):

1) Try operating the fuel filler flap. If the flap works, this will show you that relay O (E9) is getting power from the key.
2) Pull relay M (E13) to see if your Secondary Air Pump starts running. This should tell you if relay L (E10) is getting power from the key.
3) Do you have a gated car? Does the engine still crank? (with immobiliser disabled if required for cranking). I don't know if this test will be conclusive because it involves touching the key again, but this test might show if battery power is being supplied to the red wire on the ignition switch.

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Apologies

“Yesterday I tried the car and the ignition was fine on its own initially”


So yesterday I turned the key to on and the ignition came on ok without assistance from the amp leads.

I then turned the key on and off around three times, on what I think was the third rotation the ignition failed to come back on, I’m quite sure at this point I then turned the key back off and then back on again to make sure, but the ignition didn’t come back on.

I left the key in the on position after this point, and then connected the amp cables which brought the ignition back on, so yes, every time I can get the ignition going again by touching the amp cables the key is always in the ON position.

It is literally like a switch, if I touch the amp cables the ignition comes on, disconnect the cables the ignition turns off.

So i can’t just get the ignition going again via the amp cables, and then disconnect the amp cables as this will then kill the ignition again, i have to leave the cables touching.

 

Will report back in full when I can.

3) yes I have a gated car, and no the engine will not crank, the immobiliser will operate on and off as required but the engine is lifeless.

one other thing I noticed that works when there’s no power is the lights on the doors when they are open.
So when the issue is happening, the alarm, cigarette lighter, hazard lights and door lights operate still.

 

Just to make sure, as I pointed out previously I have a couple of jobs to do elsewhere on the car, but I was wanting to get to the bottom of this electrical issue before committing to those.

one of those issues is the starter motor, every now and then I’ll have to give the starter a tap in order to get the engine to crank, the ignition lights will be on and ill hear the starter click but not fire, I think this was because there was a leak in the bellhousing, I don’t want to derail the thread on a separate issue, BUT could potential oil on the starter motor be causing the electrical issue we are currently trying to fix, what do you think?

 

Thanks. I'm thinking more and more that when you did the voltage check on the amp blue wire that the key was actually working again. Not realising this threw a spanner in the works.

I think the ignition switch is faulty. Battery power is not getting through the key to either to the blue amp wire or the relay panel (via both paths). I'm not sure if it's causing your starter issues, but it certainly won't help if the ignition switch is not allowing battery power through to the ACCY, ON or START contacts.

Shorting the amp wires together feeds battery power directly to the relay panel (bypassing the ignition switch).

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Unfortunately, this is not good news. Getting the ignition lock out is a bit of a pain. You may, however, find that the contacts are burnt/corroded, so maybe they can be cleaned up.

By the way, does the ABS light come on when your ignition switch is in ACC?

Yes, these items don't go through the ignition switch. Power comes straight from the battery.

 

For the ignition switch, you'll have to purchase one of these.

https://www.ferrariparts.co.uk/part/ferrari/168045?id=10864

See item 11
https://www.eurospares.co.uk/Ferrari/355/355_(5.2_Motronic)/PartDiagrams/046/Steering_Column?ref=011

I don't know if you are aware, but when you tighten this bolt, the head breaks off and the only way to get it out is to drill a hole in it and use an Eze-Out screw extractor. It's an anti-tamper device.

 

I would still do continuity checks on the ignition switch connector (see post #36). Since the switch is intermittent, test multiple times.

 

No power, amp cables separated

1). No the fuel filler cap doesn’t work
2) no when I remove the relay the pump doesn’t kick in
3) as above, gated an nope doesn’t crank.


With the amp cables shorted
1) yes
2) yes the pump kicks in when I unplug the relay

 

Thanks for the info regarding the switch, I will have to do the tests when I return.

this is a photo I had on my phone from the ignition side of the plug, will check the other side


and to confirm, you don’t think the starter motor having oil on it could cause my issue
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So that basically confirms that no key power at all is reaching the relay panel and there is a possibility that key power is not getting to the starter relay, although the immobiliser may not be getting key power and not activating the start relay.

It would have been interesting to know if your ABS light worked, as it uses accessory power from the key.

What part of the starter casing/wiring has oil on it? I can't say I've heard (on the forum) of oil causing issues with the starter.

Anyway:

1) check the tightness of the connections on the starter and on the battery bus bar on the right hand side of the engine bay (these connections are disturbed during engine outs). i.e. in the black box marked with a red "+".

2) check for 12 volts on the small wire when cranking. If no volts, it's either the key not working or the start relay not working properly. There is an inline connector in the engine bay on the left hand side which supplies power to the small starter wire (from the starter relay), but I can't say I've heard of any issues with that one (on the F355).

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You can apply 12 volts directly to the small starter wire using a remote starter switch.

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This bypasses the key, start relay and most of the wiring. Use the engine bay battery bus bar as a power source. Don't forget to leave your gearbox in neutral.

Starter refurbish kits are available:

https://www.ebay.co.uk/itm/251718574529

It's common for the contacts to wear out.

If you need to remove the starter, remove these bolts:

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I have smaller cats than OEM, so I don't have too much trouble extracting the starter.

Starter relay is here (on a LHD car):

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You can check for voltages going to the start relay from the key and the battery. If your BRAKE warning light illuminates during cranking, that's usually a good sign that your relay is working. This is assuming your ignition switch is functioning properly and providing power to the other side of the lamp. Fuse 24 supplies this lamp power.

Note that some F355's don't have starter relays, so don't worry if you can't find the relay.

Anyway, a lot to digest. I'll wait for you to return from your holidays.