The manual calls the red light on the door exterior and the light under the door "position lights" I believe. Both my passenger door lights are not working when the door is opened. Nor is the interior light triggered. All three work on the driver's side. The passenger door window does operate correctly. I have checked both bulbs and at one point when I was checking for power in the red light socket, I triggered the interior light. However when I replace the bulb, nada ! I suspect its got something to do with the security system because I cannot understand how all 3 would be rendered u/s by a dry connection in say the door plug but there is nothing in the worshop manual on the circuitry for these lights. Any BTDT experiences would be helpful. TIA
Bad door switch. The windows work off a separate ECU in each door; that is triggered off the door handle. I haven't looked, but I would guess the alarm/lights have a separate switch that completes a ground circuit for the courtesy lights. You activated the lights by providing another path to ground while you were futzing with stuff.
Hi, The red light on the door and the interior lights are triggered by the switch on the door jamb, right above the catch of the latch. If they are both inoperable the switch is probably the culprit. Position lights in italian are what we call the parking lights in English. Saluti, Alfredo
Thanks Alfredo and Diablo. I have found that switch and it correctly triggers my wondows but not the lights on the passenger side. It does both on the driver's side. So Iam guessing that there is something amiss at the door connector at the front of the door such as a bad connection. the car has not been driven much in the rain and the connector seems unmolested so I think its long shot, with ground somewhere in the system being the more likley culprit...but where? Alfredo I agree with your translation but the worshop manual defines these lights as the DOOR position lights, which is unusual.
I have the same problem in my 456M only on the driver's side - window works properly, but the "position" lights and interior lights don't. I don't see a separate switch on the door jamb. Is it part of the catch or in a different location on my car?
I have exactly that problem. There is the central ECU, which I already replaced - not for the light of wallet! - and then there are two sub-units - not sure their exact name - one in each door. Those are the culprits. I'm having mine repaired when I go in for an oil change in February. Sorry for the inexact terminology, but my mechanic just explained it to me quickly, and I mostly just nodded my head. Cheers, Geo
Hi Did you ever resolve this? The only switch I have come across on the 456M is in the latch assembly on the door frame...this triggers the window, and I think is the door SWITCH that the 456 has as a separate component...
The circuit diagrams for this system are horribly complex. I haven't yet been able to find a link between the door ("A") pillar switches and the lights. The wiring diagrams show that the door pillar switches input into the Window Control Unit. The Window ECU seems to provide power for these switches. The wiring diagrams also show that the door lights are linked to the alarm ECU. Like the first poster, I was wondering Alarm ECU puts on the lights. However, this would involve the Window ECU talking to the Alarm ECU. The only link I could find was the command wires from the Alarm ECU to the Window ECU to unlock/lock the doors (i.e. the window ECU sends a command to the Door Locking ECU). On the F355 (depending on country), opening the driver's door will illuminate the door light of the passenger door even if it is closed (of course, this will not be visible in daylight, but perhaps in the dark, the light may be visible). The reverse is not true, however. The passenger door will not illuminate the drivers door. Is the 456 similar? It may help with diagnosis if this is the case.
After further reading of the wiring diagrams: 1) The switch on the A pillar/door hinge is linked directly to the Window ECU (pin C7 and C8) and the "door open" indications on the instrument panel. The manual suggests that it is the inner/outer door handles which trigger the 2cm window down movement (if the door is unlocked), not the A pillar switch. 2) A switch labelled "Warning light control lock microswitch" (in/on the door) in the wiring diagrams appears to control the red door open lights directly. It also sends a signal to the alarm ECU. I haven't been able to figure out what this switch is sensing. 3) The white door sill lamps (or sidewalk courtesy lights as they are sometimes known) and the interior lights are on the same circuit and seem to be triggered indirectly. This system is also connected to the alarm ECU. Still lots of unknowns. Here are my latest wiring diagrams for the windows/doors: Windows and Doors (456) Window Control (456) Perhaps someone can make sense of them.
Not according to the wiring diagrams. There is only one window ECU. On the 456 and 550, do the interior lights work if you pull on the interior door handle, but have someone physically holding the door closed?
