tinkered a bit more today.
i removed the trim panels under the windscreen that cover the cabin air intake, and cleaned the area. windscreen wipers were removed without probs. the trims were quite dirty, especially behind the edges where dirt had accumulated.
this was an opportunity to check out the cabin air intake. i have been having 'window fogging issues' all along, where all the windows would fog up on occasion. i had read about faults with the air intake flap, and also wanted to exclude water being trapped around the opening.
and...yup, the air intake flap was permanently 'closed'. this meant the cabin was permanently stuck on 'recirculate', and no fresh air was entering! this certainly explains my fogging issues. i tried to give it a nudge; it wasn't stuck around the edges, but only opened a small amount before springing back closed. now i was worried the mechanism was stuffed, and referring to the workshop manual...that's a big job to remove the entire air-heater unit!
in search of a potentially easy cause, i thought i'd find the relevant plugs and try giving them a jiggle and a clean - in case of a bad contact. the wiring is of course behind the glovebox, but easy-enough to access.
i'll be damned! what i found surprised me - a disconnected plug! the only feasible reason is that someone had previously disconnected and removed part of the assembly, and forgotten to reconnect the plug! must have been like this for years; 'fogging' was the only telltale sign of a problem, cos the 'light' was working normally in the centre console to indicate when the 'recirculate' function was (meant to be) on/off. mind you, i could never 'hear' the flap opening/closing which was suspicious, cos in most cars you can hear something. i'd also gone through the entire 'self check' procedures for the climate control, and there were no errors.
anyway, after reconnecting the plug, JOY! it was working again, properly. i'm really, really happy about this - that it's fixed, so no more fogging-up, and it was easy!
whilst pulling things apart in the cabin, i fitted a replacement LCD clock / warning panel. mine had a cracked LCD clock, so i sourced a secondhand one off ebay. wasn't totally straight-forward, cos i discovered a couple backlighting globes were blown, so i had to dismantle both (old and new), to fit the replacement unit with working globes.
i also fitted a replacement secondhand ashtray. the opening/closing mechanism had failed on mine, and was held closed using Blu-Tack!
the climate control console was removed to replace a blown backlighting globe for the 'temperature' LCD. unfortunately, the globe is unique to that assembly so i didn't have a spare, and will have to source one. it was different to the ones in the clock / warning panel, and i also have an entire spare speedo/tacho assembly, but still no matching globes.
with the climate console disassembled, i removed all the buttons for cleaning (they just unclip). and because most of them were a little 'squeaky and rattly' and hard to press, i added a smidge of grease around each button where it moves in/out of the trim piece. now each button has a great tactile feel when pressed; much improved.
so in the future, i still need to replace the blown backlighting globe for the 'temperature' display. i will also replace the Pioneer headunit - with ghastly 'blue' blacklighting - for an Alpine that i already have, and will set the backlighting to 'green'.
with the glovebox out, i also found the ECU, so thought i'd crack it open. unforunately, there is no 'chip' installed from what i can see - just what i presume to be the original. but the ECU casing clearly showed signs of being opened before (eg: retaining tabs bent), so the car must have had an upgraded chip at some stage. so the Squadra Tuning chip remains a future upgrade for me.
*dirty area behind trim pieces:
*cabin air intake on passenger side - inlet flap 'closed', meaning cabin air is 'recirculating'; 'leaf guard' removed for photo, but no air filter panel fitted (unsure if there should be one):
*behind globebox, i found the wiring plug to the flap actuator disconnected!
*with plug reconnected, the flap works like it should! fan (green) off then on:
*trim pieces cleaned and refitted:
*centre console faults:
*replacement LCD clock / warning panel; dismantled to take globes from the original to replace blown globes in the replacement:
*climate control console dismantled; unable to replace blown backlighting globe, but cleaned all buttons and 'greased' each for smoother operation:
*centre console partly fixed: new clock + new ashtray:
so would someone mind confirming:
1. should there be a panel-filter fitted over the cabin air intake? and is it unique to the 155 or shared with other models
2. my ECU chip is the factory-original?