Lights disabled by starter

[adcossey]

I got myself a 1976 RA29 Celica GT shipped to the UK from California, interior and paints completely shot but the body is good and the drivetrains known to be bulletproof. Gradually have been restoring it and have got to the engine, trying to start it this happened.



So I first took the cam cover off and adjusted all the valve gaps, gapped the spark plugs and then tried turning it over. Instantly came to life and started idling, and the cam chain sprayed a whole load of oil into the engine bay. I was so surprised it started up so perfectly after years of sitting around I did it again, the same result so I shut it off to put the cover on. I put the cam cover on and tried again, instead of starting it made a kinda click noise and wouldn't start, I tried again and this time it didn't make the click noise at all, was completely dead. The lights weren't working anymore so I figured the battery must have been on its last legs and starting it had drained it. While the battery was charging I checked in the cover, I thought maybe I'd left a socket in the head and it was jamming the engine but there was nothing there. I put the cover back on and the now fully charged battery back in, the lights came on. I went to start it, the click noise again and the lights went dead, tried to start again no noise and lights continued to not work.



It seems the lights only work if the battery has been disconnected from the car for a while, starting it then triggers something that cuts power to the lights needing the battery to be removed to reset. I don't really know where to go from this, obviously it's not a fault that is listed anywhere in troubleshooting section of manuals, but I cant even find examples of it online. Due to how repeatable it is it must be a specific failure (like a relay that's malfunctioning as apposed to a faulty earth or damaged wiring) so standard stuff like replacing the battery clamps seems a waste of time to me, am I wrong? If it has happened to anyone else I'd love to know what was causing it and how you fixed it, but if you've got an idea of what the issue could be I'd like to hear that too. Its because that it resets itself thats stopping me from just replacing the battery cables and working my way through the system

[adcossey]

Yeah, It turns easily just by twisting the fan belt

[adcossey]

Yeah someone mentioned looking at that when it first started. I took the earth wire from the battery off, thoroughly cleaned the mounting point and tested the wire for a broken connection. I've started looking into the other earthing points but I can't see how it would allow the lights etc to work (and even engage the starter solenoid) until the ignition is turned, then completely stop working till the battery was disconnected

[adcossey]

Penelope Stopit said:

Lights working, lights not working...................................What lights?

Am I missing something here?

Before I started the car I tested whether the headlights worked, after I tried starting it the headlights stopped working (till the battery was disconnected for a while then reconnected)

[adcossey]

paintman said:

Leave the headlights switched off. Don't have anything else turned on whilst trying to start it.

It isn't 'resetting itself' after waiting for a short period/disconnecting the battery. All that's happening is a very slight recovery by the battery which won't amount to much.

How old is the battery? If it has been left discharged then it's very likely it's dead & charging it won't do much as it won't be able to hold a charge.

Try a known good fully charged battery & see what happens.

The battery's brand new, It's for a slightly bigger engine (3 litre as opposed to 2.2) and is a heavy-duty 3-year guarantee from Halfords.I have tried without the lights on to see if it was a load issue but the same thing happens

[adcossey]

cheers for all the replys, I have done the following:

checked the battery, 13.9 volts between the terminals
checked the main battery earth, once again 13.9 volts between the engine block where it bolts to and the positive terminal

checked on the starter, the voltage to the positive (13.9)
checked the starters earthing (just touched the probe against the casing) 13.9 volts between battery and the casing

I removed the starter and cleaned a whole load of oil off it
took out the battery and wired it up with jump leads, all works fine both the solenoid and starter (and I guess battery)

have put it all back together, cleaned and re attached all the wires and once again checked the voltages, the same as before but it still isnt turning over

[adcossey]

paintman said:

When you tested the starter motor off the car did it just spin nicely or try & fling itself across the floor?

Bit of both, it jumped around the first time I tried so I stood on it for the second test and that held it enough to check it engaged and spun

[adcossey]

RogerDodger said:

Yep.

After charging it'll be at 13.8v then drop to 12.6v over about an hour. If you meter 13.8v then it's on charge, or, you just unplugged the charger 1 second ago .

I was testing that straight after charging the battery, that was yesterday evening but now (16 hours later) the battery's still at 13 volts

[adcossey]

I tried seeing if power was getting to the starter, I got a piece of wire and jumped power from the main terminal to the signal terminal and sure enough a blue spark and the click of the solenoid (but no spinning from the motor). I then tried jumping power to the main power terminal and once again a blue spark and the motor spun. I then went to check the fuse box, it was a bit damp so dried it off with a hairdryer, I then tried starting it and the engine turned over. Wow. I tried again and yes it was working. I then tried a third time and nothing. The lights once again do not work at all, and there are no clicks.

I have no idea why it turned over then but no other time, the battery is showing 12.6 volts so is not dead. This is getting beyond frustrating, does anyone know a mobile mechanic that knows about electrics and could sort this for me in my driveway.

[adcossey]

Auntieroll said:

Did you actually try earthing the engine block direct to the battery earth terminal as suggested by a couple of posters.?
The meter may read a believable voltage under no load conditions but if the conductor cross sectional area is inadequate under load then exactly these symptoms will occur.

Again ,as mentioned by other posters ,your new battery may be faulty.

Your knowledge is obviously lacking in automotive matters hence your post, there is a wealth of practical experience on here ,my advice would be to take advantage of it and perform the checks EXACTLY as described ,then report back.
The fault finding procedure is simple ,if you follow it.

Yeah I tried that pretty early on, the earthing point from the negative battery terminal is to a bracket that connected to the engine block but I connected a jump lead to the back of the block near the starter anyway, no change. I checked the battery earlier today, still at 12.6 volts, and switched it into my parents car, it started that up fine and plugging in a bluetooth OBD reader, the car (a Vauxhall Zafira) didn't come back with any fault codes (one would probably come up if it was dead, some extra load on the alternator etc). As I said it started up the engine in the Celica a few days ago so I don't think the fault is the battery, instead it feels like something in the wiring, possibly the load shedding relay being jammed open.

I also tried testing the battery meter, it measured 12.6 volts on the Zafiras battery as well, and testing on some lower voltage AA batteries and some button cells it measured the same as said on the packets. My das got a model train controller that puts out a variable voltage so I tested it on that and it read the same as on the LCD on the controller so I'm fairly sceptical the meter is off.

[adcossey]

E-bmw said:

In a roundabout way you have been told by several people including myself to check PROPERLY all high current connections in the starting/charging circuits, but as yet I still can't see that you have done this except that you tried to bypass the battery/engine earth with a jump lead.

Have you had every connection as above off, cleaned it, checked it & replaced them all tightened correctly yet?

Right, so I checked the negative battery terminal first, that came off completely, all of the battery clamp was removed, cleaned and put back together and tested. The positive terminal is less accessible as it goes into the loom but the battery clamp was removed and cleaned and screwed back together. The positive terminal on the starter was cleaned and refitted and the earth for it was cleaned up (the flange where the body of the case bolts to the rear engine plate).

I did mention the fusebox was kinda damp on one morning after it had rained, my next move will be to pull the connectors and clean the terminals on all of them