Led comes on but doesn't boot, screen and keyboard stay black.

Laptop was working fine, shut the lid then next time I opened it nothing happened.

I tried holding the power button to shut it off.

If I press the power button to switch it on the led on the front of the case comes on, so does the fan, for about 5 seconds. Then 5 seconds later they both come back on again but nothing else happens. No screen, no keyboard back-light.

I've shone a torch through the back but there's nothing happening on the screen so it's not booting.

The battery charges fine, I've tried a SMC reset and I see the led on the magsafe adapter change colour.

I've swapped the ram with a spare set but no different. I've removed the hdd and that works OK on another machine.

My guess is the logic board has gone but interested in any other suggestions. I read somewhere that the fan wouldn't come on if the logic board was faulty but not sure if this is correct.

crwdns2934089:0crwdne2934089:0 crwdns2934093:0crwdne2934093:0

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crwdns2944067:02crwdne2944067:0:

I see you've done an SMC reset, but did you also do a PRAM reset (Ctrl Option P and R keys)?

If that doesn't work, hold down option and S at start up to try going into single user mode, see what happens?

crwdns2934271:0crwdnd2934271:0crwdne2934271:0

Thanks for the reply, tried both of those but still nothing

crwdns2934271:0crwdnd2934271:0crwdne2934271:0

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