1.6 K series non start

[m3inter]

Hi All,

I went out in the Caterham yesterday, parked up for a spot of lunch thinking all was well with the car. However, upon trying to start her up after lunch, she just cranks and cranks without firing up.

I've had her towed home.

I was originally thinking the coil had given up as I wasn't getting any spark form the king lead when held close to an earth.

But, I've noticed the Red led on the Emerald ECU isn't turning green when cranking which makes me suspect the crankshaft sensor maybe the fault. (no crankshaft position reference, no spark!!)

I've measured the crankshaft sensor resistance at the sensor body, and I'm getting 1.2 ohm (which I would have thought would be ok?? )

Does anyone know what the resistance of a k series crankshaft sensor should be?
Or does anyone else have any little gems of info into my problem?

Regards

[Tango7]

Perhaps problems with the immobiliser causing non-firing? Seen this happen before when car worked fine until stopped for a break and then refused to fire afterwards. Owner eventually found out that he had to disconnect the battery from the car and remove the battery from the fob for several hours (a day) and then reconnect it all and it worked fine. Seemed like the immobiliser was getting itself confused and needed a full reset.

[m3inter]

Hi Tango,

Thanks for your reply. I have abled and disabled the immobiliser a couple of times. I did wonder if it could be this. No real way of testing it though. Disconnecting the battery is a good shout though. Can't hurt!!

I didn't immobilise the car when I left it so it shouldn't be so now. ie. Been immobilised and got stuck in that state (as it never got immobilised)

Would the emerald ignore the crankshaft sensor (and stay red) if immobilised?

Edited by m3inter on Sunday 9th March 20:20

[Tango7]

Not sure about the Emerald query but the chap who had the problem and had to RAC'd hone never used the immobiliser on his car at all and somehow it had become activated at Warwick Services. He tried leaving the car battery disconnected for a while but it turned out he needed to do the fob battery too for a few hours to discharge it. Hope its something as simple as this for you too.

[m3inter]

Cheers Tango,

I'll give this a go tomorrow. Fingers crossed it is that simple!

Thanks for your input!!

[m3inter]

Well I carried out a battery reset on it today. Unfortunately this didn't make any difference.

I hooked up the laptop to the emerald ECU as I wanted to see if there was a crankshaft signal being received. However, all I found was that the Ecu was immobilised.

The immobiliser was functioning ok, rather the whole control unit had become inactive! A yellow ''Ecu immobilised'' warning greeted me once communication was established with the laptop.

The only way to get round this was to enter a pin!! I had no idea what this pin was so I guessed at 1111 pressed enter and hey presto. The control unit is enabled and the car fires up!!! RESULT!

Its a little concerning why the control unit entered this mode in the first place! If its a one off, then it's not so bad, but what's to say it isn't going to do it again and again!??... Think I may have to take the laptop with me for the next few outings at least!

[m3inter]

Ok

I'll update this in case it helps someone in the future...

After getting the car running again. It once again broke down on me. It seems once its got hot it doesn't want to restart after a short rest. ( It didn't restart after cooling either)

I have no fuel entering the cylinders and no spark either.

It turns out, that despite the Emerald ECU having power, it needs 2 power supplies. I had a healthy 12.6 volt feed on one pin, but only 1 volt on the other power supply.

I traced this to the Multi Function Unit (MFU) cut this open and found 1 of the 4 relays inoperable.

If I shorted the good power supply to the faulty one the engine would run happy as larry!

Ordered a new MFU and all is well!

I hope this helps someone one day!

Regards

[Smiffy7]

m3inter said:

Ok

I'll update this in case it helps someone in the future...

After getting the car running again. It once again broke down on me. It seems once its got hot it doesn't want to restart after a short rest. ( It didn't restart after cooling either)

I have no fuel entering the cylinders and no spark either.

It turns out, that despite the Emerald ECU having power, it needs 2 power supplies. I had a healthy 12.6 volt feed on one pin, but only 1 volt on the other power supply.

I traced this to the Multi Function Unit (MFU) cut this open and found 1 of the 4 relays inoperable.

If I shorted the good power supply to the faulty one the engine would run happy as larry!

Ordered a new MFU and all is well!

I hope this helps someone one day!

Regards

Good to hear you got this sorted, m3inter. I'm due to pick up my first 7 this weekend and this thread reminded me about something the owner was telling me about the immobiliser. The car has a battery master switch and he said that he has never immobilised the car during his ownership for fear of something like this happening, and because in his words, 'the car just works every time'. The immobiliser fob simply lives in the history folder! When he is out in the car and parks up he simply just removes the master switch. Is this a common trend with 7 owners? Is the removal of the master switch as good as immobilising the car... I suppose it is?

[Right Charlie]

Yes this is very common. My SV has the immobiliser disconnected and I use a battery master switch instead. The insurance weren't bothered by the omission and it removes one possible failure mode from the list!
There is a secondary benefit to the master switch - no battery drain during storage.

[Smiffy7]

I suppose it isn't quite as secure as an immobiliser as it only takes someone else to have a red master switch. I'm assuming they are not car specific?

But together with the steering wheel removed I'm happy enough with the immobiliser unarmed