Guys Italian electrics strike again, the wipers seem to be working but only when they feel like it. What I am finding is that the intermittent and normal speeds don't work, but putting them into fast mode sometimes fires them up, which in turn then means that normal speed will work and intermittent will then also sometimes work (for a bit). I presume the wiring is from the column stalk, direct to the relay under the frunk, and then to the wiper motor itself, so 'should' be simple to check? Is that relay actually a relay, or is it a minor ECU? I'd rather avoid paying a thousand euro for a replacement. Any thoughts on how best to proceed?
Minor ECU (expensive). Maybe try for a repair? I think they are getting hard to find. P/N 153095. Same part as 456 and 550 (and early 360's) Do the wipers work when you do a windscreen wash? Different column contacts are used. Do your brake lights work properly? Is there sufficient voltage on the fuse? Tired wiper motor? 2.7 or 5.2? 2.7 diagram here: https://www.dropbox.com/t/sP46M2e6T6yJyYMu Not really sure what all the pins do.
5.2. Lights all work fine, so its not a fuse thing. On a wash, the washer unit works (ie sprays water) but again, wipers not always. It feels like a bad contact type of issue. Either a dodgy earth, possibly (but unlikely) a poor solder joint in the ECU or poor contact in the motor itself. Time to break out the circuit tester... Could just be an Italian thing and they just take August off?
Since all the switch selections take different paths to the ECU, it either has to be a power wire issue, common ground or ECU issue, not a column switch issue. Or simply a wiper motor.
Update - Earth seems fine. When I wiggle the 6 pin connector, that gets the wipers working, so its not the motor or the column. Also not going to be the column wires as they're all affected. That leaves dodgy power connection (which looks like either socket 1 or 3)...
So, got the cover off the ECU. Can't see anything obvious, and wiggling the wires does nothing, however slightly moving the 6 pin plug triggers the micro relay, which indicates (to my mind) a dry solder joint somewhere on the board, so am going to send it to a local electrics place and see what they have to say...
