EGTE 158 Posted June 1, 2020 Report Share Posted June 1, 2020 Hi guys, The gremlins are well and truly loose in my 2010 NA 😞 . First problem is the air-con stopped working a few days ago. The car was being tested all day today and it's definitely not the compressor (can be fired up electrically), or the speed-switch. We've tested many of the wires to the ECU and we're trying to narrow down the problem. HOWEVER, on the way home I had seen the drive-off-locking feature in the manual and armed it by pressing the door-lock switch for 5 seconds. Then the fuel-filler cap wouldn't open, but that's a "feature" of this system. So I turned it off, but now the fuel-filler cap still won't open! i've tried recycling the auto-lock several times but I'm completely unable to get fuel into the car. Also there is the door-open buzzer sounding even when the key is NOT in the ignition slot. Car starts and runs normally, otherwise (well it will, until it runs out of fuel).... Any ideas on this? Are there any known weak points with the wiring around the ignition area/instrument panel? Quote Link to post Share on other sites
EGTE 158 Posted June 1, 2020 Author Report Share Posted June 1, 2020 Also, some questions about the wiring diagram, if anyone can help please? 1) What sort of resistance is normal for the thermister (red box) on a 20℃? 2) Should the trinary switch be to earth, or live (green box)? 3) Same for C9 (blue box)? p.s. what is the ICM and where is it, please? Thanks in advance. Quote Link to post Share on other sites
Bruss 589 Posted June 1, 2020 Report Share Posted June 1, 2020 Icm is integrated control module . Its the ecu equivalent for switching various systems, lights, door lock, other electrical syatems. Its mounted in the fuse box in the front footwell and has four harness connection points. If nothing else it might be worth discconnecting eah one in turn and spraying some electrical contact cleaner on the connection points. Allow to dry and then reseat them. Quote Link to post Share on other sites
agentdr8 150 Posted June 1, 2020 Report Share Posted June 1, 2020 I don't see where the fuel filler flap solenoid is tied into the ICM or CDL. One side of the flap relay coil is on the battery positive, and the other side is wired to ground via the dash switch. C9 on the ICM is an output, but I couldn't find mention of if that's high or low. You should be able to hook up a voltmeter and toggle the A/C switch and see. Quote Link to post Share on other sites
PAR 278 Posted June 1, 2020 Report Share Posted June 1, 2020 Have you tried to disconnect the battery to get a full reset of the system? it solved the issue once when my car got completely gremlinsed and paralysed (auto box) Quote Link to post Share on other sites
Bravo73 1,346 Posted June 1, 2020 Report Share Posted June 1, 2020 How old is your battery? Quote Link to post Share on other sites
electro_boy 227 Posted June 2, 2020 Report Share Posted June 2, 2020 There are a few threads online with weird electrical problems that eventually ended up being a failing battery. 2 Quote Link to post Share on other sites
EGTE 158 Posted June 2, 2020 Author Report Share Posted June 2, 2020 Many thanks guys. Will continue to work on this today and yes battery was a thought; will look at it closely. Quote Link to post Share on other sites
trcm 125 Posted June 2, 2020 Report Share Posted June 2, 2020 Only slightly related, but our trusty old Saab 9-3 (used on many Alps trips) suddenly flagged up a reverse right indicator fault, then an airbag fault, then a dipped headlight fault. Oh no I thought, this sounds expensive. Put a multimeter on the battery terminals, and 9v. Gave it a long slow charge and all is well again Why manufacturers dont have a low-battery alarm I will never know.... Quote Link to post Share on other sites
EGTE 158 Posted June 2, 2020 Author Report Share Posted June 2, 2020 Thanks, I hope that fixes it - CTEK working hard right now 🙂 2 Quote Link to post Share on other sites
EGTE 158 Posted June 4, 2020 Author Report Share Posted June 4, 2020 Well it's not the battery, sadly. Have jury-rigged two wires to the fuel filler-cap to activate the solenoid with 12v if needed. Tested the compressor and it works fine if powered up separately. I'm guessing that somewhere in the loom from the dash area back to the engine there's a loose connector/wire......will 'enjoy' tracing that over the next few days. The common part I can see in both diagrams is the busbar; anyone know where the connectors from that are? Quote Link to post Share on other sites
EGTE 158 Posted June 4, 2020 Author Report Share Posted June 4, 2020 LOL the fuel filler-cap was down to a loose relay; they are right next to each other in the rear fuse-box panel and in swapping them over for testing, the filler-cap one wasn't quite clicked into place. One less drama, but a tad embarrassing ☺️. So.....back to the air-con only: Does anyone have a clue where the ICM is physically situated at all? Thanks @agentdr8 for the comment on C9. 👍. Do any of you whizzes know the whether the trinary switch be to earth, or live (green box)? Don't want to fry the ECU....... Quote Link to post Share on other sites
Bruss 589 Posted June 4, 2020 Report Share Posted June 4, 2020 I think its in the same place as I said above. Unless its moved. Quote Link to post Share on other sites
EGTE 158 Posted June 4, 2020 Author Report Share Posted June 4, 2020 Oh sorry , missed that Bruss, thank you. Quote Link to post Share on other sites
agentdr8 150 Posted June 4, 2020 Report Share Posted June 4, 2020 Assuming you found the ICM, the output from C9 to RC1 on the EMS ECU seem to pass through. No indication of what level of signal is being passed. Some ICM outputs are grounds, some are +12V. Testing it with a voltmeter should be relatively safe; with the A/C switch on, if you have your black probe on a body ground, and your red probe on C9 and no voltage is shown, then it's likely a ground output. Switching to continuity test, once the A/C switch is turned it, if it's a ground output it should beep. Conversely, if it's a +12V output, you should see that indicated on the first test, and there'd be no need to test continuity. If you want to remove the trinary switch from the equation, you can just put a jumper on the harness side pins for that connector. One thing to note; your green box is only half-correct. It actually should encompass the "TRINARY SW COOLING FAN" beneath it, as that's all one unit (a binary pressure switch + a unary fan switch == trinary switch). There's actually 2 separate connectors for the different "sides" of the switch within the unit. Here's a picture of one I found for our cars: Since Lotus updated the part number, it looks like they may have also updated the wiring colors from what's stated in the wiring diagrams. Might have to figure out which connector is which by pulling the front right wheel well cover. Quote Link to post Share on other sites
EGTE 158 Posted June 5, 2020 Author Report Share Posted June 5, 2020 That's brilliant information, thanks @agentdr8. Quote Link to post Share on other sites
EGTE 158 Posted June 25, 2020 Author Report Share Posted June 25, 2020 Sitrep: the cooling fans aren't working either. I had ordered a new Trinary switch but it looks like it might be an ECU problem, as we can find any faults from anywhere until we get to the ECU 😬 Does anyone know of anyone that can inspect/repair an Evora ECU? Quote Link to post Share on other sites
agentdr8 150 Posted June 25, 2020 Report Share Posted June 25, 2020 I think only someone with the Lotus TechCentre. Quote Link to post Share on other sites
EGTE 158 Posted June 26, 2020 Author Report Share Posted June 26, 2020 Okay, thanks. Quote Link to post Share on other sites
EGTE 158 Posted June 30, 2020 Author Report Share Posted June 30, 2020 ECU reset and all fixed! Gremlins in the ECU.... Quote Link to post Share on other sites
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