348TS fuse box connector schematic

Guys, I am a new Ferrari owner. I purchased a '91 348TS and have been doing a bit of restoration on it. After the engine out, the car wont start. We have been doing several tests and have arrived at really needing the pinout schematic for the plugs in the back of the fuse panel. I'd go into further detail but it's a bit of a long story. Do any of you have the schematic that would show color and position of each wire in the connector? I have the schematic that is from the workshop manual but I do not see wire colors in it. Although its possible I have missed it, its a bit hard to read.

 

This one?
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Won't crank or won't run?

Here's a diagram with the starter motor in it:

https://www.dropbox.com/t/iq9ZWmYcU5gnhuM9

Note the graphic of the rear of the fuse panel in the top, right hand corner

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The wire colours are written on the original diagrams in one or two letter Italian colour codes.

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Here's a full sized diagram of Ferrarium's diagram for the Motronic 2.5 engine:

https://www.dropbox.com/t/498EgyRfcnC2c3ZF

 

Was it running before? Isn't it most likely that something hasn't been reconnected after the restoration?

 

At this point, I am not going to say what is and is not possible. We are going through diagnosis now. Once we figure it out, ill recap for everyone. Hopefully someone else can learn from our work.

 

There have been several problems we have been working through with this car and we have solved one major issue. Now, the problem is, we are getting no injector pulse when trying to start the car. This problem is with both banks and all injectors. We have had the fuse box out of the car. We have verified that the Injector and fuel pump relays function (as a stand alone relay) and that the box is sending and receiving proper signal on all four circuits. When moving to the Motronic connector by the ECU's we can verify continuity between those connectors and the fuse box. That however is where we are stuck.

If we look at the wiring schematic it is not obvious where the connectors are listed that go the the fuel injectors. We see each the schematic showing ground being controlled by each ECU and the power wires going to splices (or "two ways connector). However we have no continuity between the Motronic connector and the 7 pin round connector going to each injector bar. Can anyone tell me what these connectors do? Do they supply power or ground? Also, can you tell me where they are listed on the schematic? The car side of the fuel pumps and injectors are functioning as they should. Both on the control and controlled sides of the circuits. We have power to the pumps, the coils are firing, but nothing at the injectors. We need to continue our electrical checking but are at a bit of a standstill because the injector harnesses are not obvious on the schematics.

 

Not sure what you mean by all four circuits. Are the ECUs sending an earth to their respective (D & L) relay coils. These relay coils are energised when the ignition is on and that each ECU has passed its brief internal check.

I'm not sure if these connectors are round or rectangular on the 348. The equivalent of these connectors on the 355 are rectangular and mounted on the engine cradle close to the ECUs.

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On the 355, the mounted half of the plug goes to the engine components and the loose plug goes to the ECU. It's probably best to ask the folks on the 348/355 forum about these plugs.

These 118 and 119 connectors should be receiving power from relays D and L on pins 3 and 7. Is there also no power at pin 3? (ignition on)

Do you have an aftermarket immobiliser?

 

I meant to say .. "and after each ECU has passed its brief internal check"

 

I'm still not sure which round plug you are referring to. The only connectors attached to the injectors are the 55 pin ECU plugs and plugs "118" and "119" (12 pins?)

Just realised that the "118" and "119" connectors are in the cabin, near the ECUs.

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The upper half of the plug (sockets) goes to the ECU and the injectors. The lower half (pins) goes to the relay panel. Are your plugs 12 or 13 pin?. The Motronic 2.7 car lists 13 pins, so I'm not sure if the plugs are the same shape/configuration as the 2.5 car.

 

Ian, that picture shows the internal of the 348. The Mondial T has two ECU in the trunk. All the connections are easily accessible from the rear trunk of the car.

Mebozart, if you are really up a creek and need to verify something, contact Paul Chua on this board. He has a Mondial T and is very willing to assist.

 

Also, there will not be any ignition if the TDC / RPM sensors are not sending any pulses to the ECUs.

 

Do you mean on the Mondial, Mitch?

Do you know what Mebozart is referring to when he says

I know on the 456 and 55o there is an additional round connector feeding the injectors only. I haven't see one in the 348 diagrams.

He says he has spark, so that's a good sign that the crank sensors are working.

 

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@mebozart

Thanks for the photo. I have no idea what that is. The 2.5 parts diagram shows individual leads going directly to each injector from the ECU harness.

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On the 2.7 engine, component #5 looks like the item in your photo?

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(EDIT: Is it possible you have a 2.7 engine?)

 

Just wondering why there are 7 pins. You'd need one pin for power (#3) and 4 pins for the injectors. What's that extra (small) harness for?

 

There is a diagnostic chart available for the 2.7 engine ECU:

https://www.dropbox.com/t/KaKKHoOARKOgZZQA

What you could do is check the resistance of the injectors from the main ECU plug (on each bank).

e.g. Check the resistance between RH ECU connector pins 17, 34, 16, 35 and pin 37 (earth) on the left bank (value 16 ohms +/- 4 ohms). I mean the detachable half of the plug.

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This is with the all injector stuff hooked up of course.

Repeat for the left bank.

This will prove that your injector trigger wiring is ok. You know you have power at the injector rail round plug, but it wouldn't hurt checking the individual outputs on that . I guess you would then have to remove that injector rail module (in your photo) and check for power at the 4 outlets (with the ignition on and the round plug connected).

Regarding the two pin connector on that device: There are a number of the Bosch connectors on these cars. The F355 is known to not start if these plugs are accidentally swapped. The only way to prove that the plugs are not swapped is to run through the diagnostic chart (linked above).

 

If you have time, it would be great if you could match the pins on the 7 pin round connector to the ECU pins shown above (17, 34, 16 and 35).

 

Part #5 that clips to the injectors with the round plug is actually a BMW part.

 

Mine still have the actual blue BMW label on them the bottom side.
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Eric, do you know where that extra plug on part #5 goes to?

 

Yep the plug that goes to bracket 7 is under the intake manifold in the rear straddling the oil filter which goes to the harness. The other one which is blue to the coolant temperature sensors on either side.

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Thanks, Eric.

Just wondering why none of the OEM wiring diagrams show this setup.

 

this was the problem we ran into. I can tell you that there was a single 12v wire and all grounds in that 7 pin connector. I can ask my tech tomorrow for location of the 12V. Any of you keeping updated wiring diagrams can add it.

 

As much as I'd like the pinout for the plug, Matt, don't waste your time and money getting the tech to run checks