To try and keep the history record reasonably complete, I’ve copied most of this across from another thread.
Having left my vehicle sitting unused for a few weeks, and covered in snow, I thought it best to get it started and charged up. I should never have been so lazy as to leave it so long. First problem was getting in it since the lock handle was frozen and not budging. After overcoming that particular issue, rather predictably, when turning the ignition key to II, as well as the glow plug lamp coming on, so did the ORM/SLS lamps, so clearly the battery voltage was way low. Not cranking of course, so I switched to my aux battery only to find that although it had better charge, it was still too low to get the engine started. I turned off the Heater/AC unit before cranking so that I had nothing else drawing current when first cranking (not that it would make any difference).
I got my NOCO Genius battery charger connected to my batteries and put it on charge then set to work digging SWMBO's Astra out of its own snow tomb. After an hour and some, I checked to see if the Td5 would turn over; it did and fired up. Now, with the engine running (NOCO still connected), I pressed the 'on' button on the climate control module; nothing, it would not turn on. I tried a few times, but it wasn't coming on. Typical I thought, get it running to defrost the vehicle and the blinking heater stops working. I had a look at the electrical library and circuit diagrams but I wasn't seeing anything obvious (I was hoping for a fuse).
I'd left the engine running to warm up and still charging, so after another hour, I tried the heater again but still wouldn't switch on. I turned off the ignition and decided to leave it on charge and forget about it for now. However, I decided to turn the ignition key to Pos. II and try the heater again, and low and behold, it comes on: start the engine again and the on/off button doesn't work again.
I don't know what I've done to deserve it but the plot then thickened. A break in the weather allowed for a look at my problem. I checked and replaced F23 (and F20) in the passenger compartment fusebox; fuses both good. When I turned ignition to Pos.II, the instrument cluster lit up and the self-test completed, I could hear the fuel pump running and all seems normal. After the glow plug lamp went out, I turned key to Pos. III to crank and nothing; dead as anything! I could hear a faint click from behind the ignition barrel area but nothing else. Now I went to get my multi-meter only to discover that it's not working, and waste time trying to fix it to no avail, so no multi-meter available to check the relay. I had a quick look in the engine compartment fuse box and manually/visually checked the relays and fuses, but nothing visible. I then climbed underneath and made sure the Lucar spade connector was tight on the starter motor. Finally, I hauled out another battery and tried a jump start in case, but that didn't work either.
I was confused and now worried that I have another failed BCU. The fob locks/unlocks the vehicle, the heater blower is now working fine and the on/off button on the AC control working; it's just that dreaded dead/no crank issue. It started to rain again, and I was getting wet so I called it a day.
After a short delay, I went back out with a posh new multimeter and a relay bridging wire. The relay was good, I bridged the relay sockets on the fusebox but no crank. FL12, FL8 and all fuses good. Then would you believe it, it started to rain again. It was too cold and wet to be crawling around it so back in the warm. I put the battery back on charge for good measure. FYI, my battery tester passed battery as good, so looks like starter motor relay/solenoid issue I guess. I had already checked the Brown/Red wire to that spade connector but that was about all so far. Time to order a starter motor repair kit.
It was at this time that my Mum was taken into hospital where she was kept in over the New Year holiday, and having to stay up in London, and the constant rain and poor weather, I didn’t get a chance to deal with the cranking problem. I had the starter motor kit sat ready to fit, my new all singing and dancing multimeter ready for action, and the noco genius has been keeping the batteries topped up. But, finally, although still freezing cold, I was able to venture out to do the start relay voltage check; it's been nagging away at me that I might have a wiring issue and not the starter solenoid contacts causing my problem. Well would you Adam and Eve it, the key fob isn't working now! I opened the door with the key and put key in the ignition and of course, red led on constant and immobilised (not that it was cranking before anyway).
I give up! I've never had trouble with the RF receiver before or with my key fob, but while it's been sat for weeks with constant rain and cold, it's all gone very Pete Tong. I noticed that the roof was absolutely dripping wet with condensation
(my roof lining is off) so I'm guessing it's the RF receiver. I really couldn't be bothered to investigate further as I was both freezing cold and depressed.
When I next got out, I checked that voltage and it read 7V; what in heaven’s name is going on? Looks like a new fusebox then as this makes no sense (which will be easier to deal with than the starter motor at least). I will need a new RF receiver too as it fails the RF test. The condensation on the roof is so bad that there was a puddle of water on the dash.
No wonder the headliners fail the way they do.
After ordering the parts I needed from Heathy, I got back to work. Seems it was the starter all along. I’m really not sure what was going on with the odd voltage readings before though; I'm totally confused. Having ordered a new fusebox and RF receiver, I fitted the receiver (inside a rubber glove ) and that fixed the locking/immobiliser issue. Before fitting the new fusebox, I decided to check continuity from Battery +ve through to the 12V out (NR wire) that goes to the starter solenoid; it was open circuit. Now, I had checked the fuses and fuseable links when I first started trouble shooting this problem, so was confident that all fuses were good. This is what led me to conclude that my problem was with the contacts inside the starter and I ordered up a repair kit. Finding now that I had no continuity, I thought that this confirmed a fusebox internal problem with the path from The 12V input (the thick brown cable) through to the relay. However, this seemed a bit unlikely when looking at the box and so I re-tested the link fuse F13. Well, surprise surprise, the link fuse was OC! I'm clearly going mad as I'm sure it was OK when I tested it before. Suffice to say, I replaced it and restored continuity to the SM relay.
It was still dead when turning the key to crank, and bridging the relay still does nothing, but I now had 12V across the relay socket. Back where I started then with a suspect starter motor.
I got the starter out and tested it on the bench,
the solenoid operated fine when I hooked it up to a battery but the motor didn't run. I put 12V on the motor direct and it ran, so right back to the original prognosis of worn out contacts (the kit I ordered to begin with). Didn't take long to strip out the old pitted contacts, clean up, and fit the new kit.
The starter now runs fine.
Put it back in the vehicle and confirmed it now runs again. Cranked and started no bother.
I went for a test drive and it's running OK. Only thing is, where it's been sat in the cold and the rain, I now seem to have one front indicator lit up permanently and water dripping down inside from all that condensation.
BTW, getting to the top nut on the stud that holds the starter motor in place is one absolute bar steward of a job. There was no way I was able to get at it from underneath, I could barely get my hand anywhere near it. I had to go in from above with a very long extension, a cardan and 15mm socket. This worked to get it undone but I haven't been able to get it back on. There isn't enough clearance to get the socket in straight enough to start the nut on the thread.
After all of this anguish, I then worked out where I went wrong on this. The D2 TD5 Electrical library says Fusible Link FL 12 is for the starter relay and that would have been what I checked and found good. But when I was doing my continuity testing, I pulled FL13 and found it was blown. I now realise that I pulled FL13 as that is marked SM on the fusebox cover legend. I must have gone out to test it before after checking up the library and gone straight to FL12 and not realised I was testing the wrong link!
I now have a spare engine compartment fusebox
It was never going to be so simple though, I knew it was too soon to relax. Seems I still had an issue. I now had a problem where the fob only worked if I stood by the rear passenger door, held the key up against the glass and pointed the it directly at the receiver with the fob touching the glass; it had no range! The fob does work now with the replacement RF receiver whereas it wasn't working at all with the old one, but only up close as I've described. I had dried out the roof area and fitted some insulation as well as cleaning the bolt hole for the receiver earth, the bolts, and ensuring good earth contact before fitting the replacement receiver. Heathy is sending me another to fix the problem or at least rule out the receiver.
I hadn't realised until looking closer that I actually have the RF receiver with 3 wire connector, i.e., an earth wire, so I'm not clear if the bolt to roof earth is actually relevant: Fed up now.
Paul (Heathy) made sure a replacement was with me the following morning. After fitting it, all was good again. I can stand across the street in my neighbour’s garden now and the fob works fine.
A long and very annoying problem to diagnose and put right, yet one that should have been very simple. Something just doesn’t make any sense though, and that is how could I possibly have gotten a reading of 7V across the starter relay socket if the fusible link was blown? Voltage coming back from the starter somehow? And why then did I get 0V next time I checked it? A mystery.