Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Aero - not starting due to clutch switch.

Chaps - below is exerpt from my e-mail to BHM. Since found to be clutch switch:

"Car parked at one pub after long run. Left for 2 hours. Starts perfectly. Driven to and parked in another pub car park for an hour. Will not start. RAC called. While engineer is fiddling with fuse box, car starts. We think that the starter motor relay may be sticking. After this, starts again repeatedly. I then drive it for an hour, stop it to put petrol in it. Starts fine. Drive to friend’s house, where it is parked overnight.

Starts fine in the morning, 2 hour run through London. Park it at my girlfriend’s house. It fails to start. I fiddle with the starter motor relay, still won’t start. I check all the fuses again, all fine. RAC arrive again. Check the starter motor relay – and it seems to be clicking when I push the start button, so it appears to be something else. We gently try to bump start it – thus bypassing the starter motor – it still won’t start. Put it onto a low loader, bring it back to you. Get it off the low loader, it starts fine.

I would think that it was a hot start problem, except that as you can see, it has started while hot on a number of occasions. It’s not the starter motor assembly itself – car still wouldn’t start even when we bypassed this with a bump start (although we couldn’t confirm this by getting direct power to the starter motor due to it being inaccessible – you could try this and check the connections when it’s up on the ramp). It’s not fuelling as the engine won’t even crank when the fault appears.


I think it is either:

- ECU; can you reset it, or does it need to go back to Malvern for this?
- One of the sensors tied to the ECU
- One of the switches required for starting being loose – inertia switch, clutch switch etc
- Immobiliser"

It turned out to be the clutch switch.

I think the reason it wouldn't bump start is that the clutch switch doesn't operate on the starter motor circuit per se - it operates on the engine management. It is not a simple switch, but rather a magnet/circuit board combination that when you depress the clutch bring the magnet and board together, thus doing something that tells the engine management that you can start the car.

The part itself isn't expensive. According to Keith at BHM, getting the pedals and associated bits out to get to it is at least a couple of hours.

So there you go!

Frustrating though, isn't it?

Mine overheated twice in the first few days due to different faults.

Both found & fixed by BHM promptly, but having a brand new car returned to garage on low loader is a bit worrying, especially as we nearly took car straight off on a long holiday following collection.

Are you sure... i.e have you changed it and it is Ok now???

I had exactly the same problem last year and it turned out to be something even simpler and a recurrign S1 fault.... underated starter relay fuse. Mine went intermmittent and was really hard to spot as blown or not. If your starter fuse is 20A then change it for a 30A and save yourself quite a few pounds.

BHM seem sure - they swapped it out and put the magnet back into the right place and she started every time - and she's had a 30amp starter relay fuse upgrade already. All fuses were fine when it broke down - so I knew it was something else...

Bugger of a job to change this switch, apparently...

I think this really is a case of too many electronics; why a magnetic induction microcircuit when you could either:

a) use a microswitch, or
b) not bother with a switch at all, trusting people to not start their cars in gear.

I guess it would have been too much hassle to re-engineer the X5 electronics, designed to stop school run mums from accidentally running over their offspring when starting up their battle tanks...

Great... just checking the know faults. I phoned a well known dealer (not BHM) when I had my problem and they never even mentioned the fuse - despite the factory putting a note out about some time before.

Absolutely! Sort of destroys your confidence in the car (given that one of my major reasons for choosing an Aero over a much cheaper and somewhat quicker TVR, or indeed a more expensive but more iconic Ferraris F355, was its perceived reliability). As I'm about to drive it down to Monaco for the GP, I need to spend next weekend doing a lot of UK miles to build up some confidence in my Aero, I think.

Keith at BHM is running it as his commuter for the next few days to properly test it!

Not this morning, it looked like a SAAB....!

Hoping that he's not leaving it at work because he doesn't trust it...

Sounds like a very good idea... what with the sun and all

Part not in yet, Keith was hoping it would arrive today...didn't.