1997 F355 Will not start. Calling all Ferrari doctors

Make sure your OBD2 port has the wiring update:

The port should have earth (black) wires on pins 4 & 5

 

There are none to swap.

If you jump the relay, the car still won't start because the injectors won't fire, but at least you will hear the pump operating. The key must be on. The idle air control valve can be a little noisy making it harder to hear the pump, but you should be able to hear the pump stop and start.

Jump these pins (or rather the relay sockets corresponding to these relay pins)
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If you have a voltmeter, check power on the pump fuse when you are cranking the engine. i.e. with the relay fitted. The fuse is downstream of the relay.

 

Is what you are showing the starter motor relay or is this the fuel pump relay? Nothing on the floor board diagram shows a starter or fuel pump relay. The right most relay (not on fuse block), I believe is the starter relay. I jumped it and the car cranks but can’t hear the fuel pump kick on and not seeing any voltage on the LH Fuel pump fuse. There is also a RH fuel pump fuse(not sure why).

 

It's the fuel pump relay. Your car is cranking, so it's not a starter issue.

If you have a starter relay, it will be bolted next to or on the relay panel, not plugged into it (I think that's the one you found). Anyway, it's not a starter relay issue as you have cranking.

For the fuel pump relay, look for "E2" printed on the relay panel. This is relay "N" in the workshop manual or Owners Manual. But first make sure you have a 5.2 engine. If your car is definitely a 5.2, then you shouldn't have two pump fuses or relays (The fuse will be a spare).

If you have a 5.2 car, your relay panel will look like this:

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Start relay not shown. The fuel pump fuse is labelled "21". Fuse 22 should also be powered if the fuel pump relay is operating normally.

With no power to the fuse, it means that the ECU is not sending a signal to the relay (assuming the relay and wiring are ok). Try jumping the fuel pump relay to see if the pump runs (with or without the key on). That will prove your pump is ok.

 

Just rechecked the wiring diagrams... Pin 30 of the relay is live, so you should get pump operation with the jumper (even with the key off)

 

Correction. The car will run if your ECU is operating normally. I'm still not sure if it is ok as I don't know if it's enabling the fuel pump relay.

 

If your fuel pump runs with the jumper on the pump relay, you could look at the following:

1) Pin 87 of relay M should provide power to the coil of the fuel pump relay. I can't remember if that's pin 85 or 86 on the fuel pump relay. You could check this with a continuity check between the two relays

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Unfortunately, I can't check this on my car as it's undergoing a major.

I know your relay M is working because you have a Check Engine Light on. The CEL needs power from relay M. However, doing a continuity check between the two relays will show that there are no issues with the relay panel pin connections.

2) During cranking, the ECU sends an earth/ground to the other side of the fuel pump relay coil (86 or 85?). You may be able to simulate this by backprobing a plug near the ECU. First let me know if your fuel pump works with the jumper.

 

It may also be a good sign that your immobiliser is ok. I don't have a full set of wiring diagrams for the all F355's, but I believe that on all 6 speed cars with start relays, the immobiliser controls the starter.

My start relay is on the far (bottom) left of my relay panel, but my car is RHD. On RHD cars, the panel is upside down.

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Note that the "Segnalatore Acustico" to the left of the start relay is a spider feature.

If your fuel pump runs with the jumper wire (and assuming it is producing good pressure), the issue is probably a crank sensor, but it won't hurt to do some basic wiring checks to save money.

 

Thank you for the extensive information and support! I will test more this morning.

 

Yes, fuel pump runs with relay N jumpered.

 

Sounds good. So, assuming the fuel pump lines are not gummed up with rubber debris, you should have pressure at the fuel filter and fuel rail.


(EDIT: I was going to suggest shorting a pin of a certain plug to earth to simulate a signal from the ECU to the fuel pump relay, but it wouldn't work. Disconnecting the plug would remove power from the ECU and the ECU wouldn't activate relay "M")

Anyway, you have to figure out if the signals going to the pump relay coil are ok. When you turn on the key, do you get 12 volts on the pump relay socket pins 85 or 86?

 

i.e. red probe on one of the pins and the black probe on a good chassis earth. Note any voltage changes before and after you turn the key on/off. Normally there is a delay in power removal after you turn off the key. Wait for the car to go dead.

Ideally, to check the signals going to the pump relay coil during cranking, you would need some kind of test light.

https://www.amazon.com.au/Haobase-Electrical-Circuit-Continuity-Indicator/dp/B081JLJHD8/ref=asc_df_B081JLJHD8/?

The resistance of the incandescent light in the tester simulates the resistance of the relay coil. i.e. it puts a load on the circuit.

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Nowadays, many of these testers use LED bulbs which the ECU may not recognise as presence of a load (simulating the relay coil). Some testers still use incandescent bulbs but one of these I have seen uses a 3W (250 mA) bulb which may overload the ECU circuitry controlling the relay which, typically, draws about 150 mA. The ECU should have protection against overloads here but I did not want to take any risks and I made this test light using a miniature 12V bulb which draws just 50 mA. This was sufficient to "full" the ECUs on my 348 and was very safe.

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I see some 12v 50ma bulbs come with really long leads. You wouldn't even need test leads in this case. You might be able to plug it straight into the relay socket.

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We have a no spark condition, fuel system is working properly. Any ideas of what would cause no spark? Hooked up multiple styles of OBD2 code readers and cannot communicate or not getting any faults. SD1 may be the only option with taking the dreaded dealer to diagnose.

 

What do you mean by “fuel system is working”? Did you get your test light to illuminate continuously when plugged into the pump relay (showing that the ECU is sending the enable signal during cranking)? This also shows that your crank sensor is working.

Do you have 12v power at your coil packs?

Crank sensor or crank sensor wiring failure, no ignition power to coil packs (wiring issues), ECU internal fault….

Are you turning off the immobiliser before attempting to use the OBD port?

 

Key power is supplied to the middle pin of each coil pack. Key power goes through the relay panel where it splits into two paths (R and L coilpack power). The LH branch also sends (at least one source of) key power to the Motronic ECU.

This key power goes through engine harness plug 41090. Plug 41090 is the 9 pin plug near the ECU. Issues on this plug are not unknown (as the plug is dragged through the firewall during engine outs). Pins may be bent, corroded or loose.

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Pin 2 = yellow wire/ RH coil pack
Pin 3 = yellow/black wire - LH coil pack and ECU

If the engine has been installed, these plugs will be in the cabin.

 

Immobilizer is turned off prior to code read. I used a Foxwell 680 Pro, it was able to communicate and ran through all the tests with no faults. Yes, fuel pump runs with relay N jumpered (is this what you were referring to?) I will check the connections and any loose pins on the ecu connectors.

 

No, I mean the check mentioned in post #62, #63 and #64. This confirms that the ECU is sending the signal to the relay to turn on the pump... and also checks that your crank sensor is working (if the test light stays illuminated during cranking).

(EDIT: The test light may illuminate for a couple of seconds when you turn on the key, prior to start)

If you're just jumping the relay, it's only checking that the pump operates with direct battery power.

 

Update: Brought car to Ferrari of Greensboro Foreign Cars Italia), ECU would not communicate with SD1 computer. Was told possible ECU failure ($8k+ for new plus install and testing. Decided to have ECU/immobilizer/key fobs sent to Specialized ECU Repair in FL. They tested all parts. ECU and key fobs are good, one immobilizer module faulted. Recommended to install immobilizer bypass, once installed all tested good at repair facility. All parts sent back to Ferrari for install and car starts perfect. $850 for bypass and testing. $1800 for Ferrari labor.

 

Thanks for the follow-up. I wonder what module was faulted.

Not that it matters now with the immo disabled, but did you find out if your car has a starter relay? Usually that is Immo-controlled.

 

Yes, it has a starter relay but Ferrari did not do or try any troubleshooting which was quite disappointing.

 

I had a car once that would do all the things yours does (crank, accessories worked, but wouldn’t turn over) turns out the battery had a couple of dead cells that prevented the electronics in the run circuits from receiving power even though everything else was fine. Don’t ask m to explain it, just throwing it out there in case it helps.
-Mark

 

Some shops have to monitor the amount of time which can accumulate while chasing electrical issues. The diag can take days and dozens of hours. I have an issue investing the time needed and eventually conveying to the owner he's $5K into diag and the car still does not run. Additionally I'm discovering the parts needed for repairs are becoming increasingly difficult to find.