355 Rear side markers reflectors on 355 bumper signal?

This is not normal. The wiring for the Euro car is different. I'll post some diagrams shortly. I have recently acquired a set of F355 USA paper workshop manuals with black and white wiring diagrams, but I forgot to update my coloured diagrams for the USA car.

Which car do you have? 2.7 or 5.2?
Most likely, you will have to cut a wire for the turn signals somewhere and put a splice in the marker light wiring. I had a problem with brake lights flashing with my turn signals, a grounding issue, but yours is a different problem.

Cheers
Ian.

 

When you installed the Euro bumper was it a 5.2 bumper or 2.7 bumper and did that include the tail lights? Did you then install illuminated side markers in the Euro bumper?

I didn't realise the early USA cars didn't have side markers.

 

By early, I mean '94. The '95 model introduced side markers, changed the tail lights and removed the side turn repeaters. Or did no '94 models make it to the USA?

 

Sorry, I'd better start from scratch... I was thinking you fitted the whole rear of the car, not just the bumper.

Strange. The manuals I bought were supposedly for the American market and all '94 cars had no side markers.

I didn't realise the US cars had reflectors as well as illuminating side markers. Or do you mean the reflectors in the centre element of the outboard red rings?

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Perhaps it is an earthing issue. Do you know where the earths are for the rear lights and side markers? Have you double checked the lamps are correct for the outer red rings? i.e. dual element and that they are all working?

 

I think Ian is correct when he says it mat be a grounding problem. Speaking from experience, though not on a 355, a bad ground to a tail light or some other indicator light can cause all types of havoc. Most recently I had a bad ground to a brake light on my Toyota ruck. Every time I stepped on the brake the 4 way flashers would start going. If I put on the left turn signal the brake lights would go on.

The thing is, so many of these things are connected to a common ground that main ground fails current will find another path to ground through other circuits.

 

There are earths on either side of the car for the respective L/R clusters. The diagram above is labelled incorrectly. I meant to say the grounds are slightly above the upper support bolt on each radiator.

Anyway, here are the diagrams for the earlier cars...

Euro Lighting Diagram (2.7)

USA Lighting Diagram

 

There is no such thing as a MY 94 355 in the US. They started coming to the US In 94 as MY 95 and with everything required by DOT and EPA to be sold in the US. Marker lights, airbags, etc.

 

Here's the 5.2 USA diagram.

USA Lights (5.2)

 

Qavion said it in post #2, this is absolutely not normal. Only the side in which you are signaling should flash.

 

Ugh.. Now I'm confused (again). I thought the US rear marker/turn lights would have bulbs with dual (separate) elements and the circuits would be isolated (other than common earths).

I still don't know what you mean by "reflectors". A reflector to me is a bit of plastic or glass which catches light. It is unpowered. Although all lenses on the F355 reflect to some degree, I would only classify the white centre of the rear outboard rings on US cars as "reflectors" as they don't have bulbs in them. (o)(o)____(o)(o)

I know the US cars have small rectangular orange "marker" lights on the sides, front and back, but I assumed they were just steady lights and didn't flash at all.

Perhaps our resident guru, Miro, can explain why the rectangular lights flash at all. Of course, having both rectangular side markers flash is abnormal. It would confuse everyone.

I was going to recheck the behaviour of my Euro/Australian lights, but found I had a flat battery...

 

This thread is driving me nuts. Simple question that no one seems to have bothered to check. So I tested my car. 95 US version. Already knew the answer. The side markers, front and rear, left and right DO NOT FLASH UNDER ANY CONDITIONS. They come on with parking lights and head lights and remain on STEADY, whether the turn signals are activated of not.

THE END!!!!!!

 

This is a clear indication of a bad ground or other wiring problem. I bet if you look closely, then the parking lights are on, the side marker is not turning off but just becoming very dim when the turn signal flashes on, because the current is finding a lower resistance path to ground.

[edit] there are some other scenarios to, but hared to explain in type.

 

Thanks John! I was starting to doubt my electrical theory.

Back to basics. Ruey, are your side markers (front and back) flashing or just the ones at the back)? For the sake of conformity, let's call them "side markers", not reflectors

If there are single element bulbs in your tail turn/marker lights, and there are supposed to be dual element bulbs, I can see how the side markers might dim when the turn lights are flashing. Ruey, if you have time, can you check your rear outboard (red ring) lamp _holders_ to see if there are two contacts (not including the earth). If so, do your lamps have two contacts on their bases?

Sorry, I don't know the part number of the lamps or if they are coloured on US cars, but for those who don't know, dual element lamps are like this:

https://mechanics.stackexchange.com/questions/20925/how-does-a-lightbulb-with-two-filaments-know-which-one-to-light-up

If someone has a part number, I can add it to my wiring diagram.
Supposedly, the offset locating pins on the lamps should stop you fitting the wrong type.

Did you find the earths at the front corners of the engine compartment, above the radiators? The left side is much easier to find on my 5.2 spider. The right side you have to feel around for.

 

Yeah, after rereading some of the posts between tail lights, “reflectors”, and side marker lights I was a little confused on what we were talking about when I answered too.

 

Ah, ok. I wasn't familiar with US history I was using the terminology in the USA Ferrari Workshop Manual