No start - 986 Forum - The Community for Porsche Boxster & Cayman Owners

pastey123 · 10-19-2016, 03:38 AM

This past Saturday I went to the gas station and when I went to leave the car would not crank when you turn the key. I thought it might be the ignition switch I replaced a few days prior that might have gotten loose so I disconnected the battery and reached around to see if the connector at the end of the switch was on right. It was connected right, so i reconnected the battery and the car started up after trying a few times. I drove for about 30 minutes and went home.

When I got home I tried starting it again and wouldn't crank, no matter how many times I tried. I put back the old ignition switch and got it to turn on a few times consecutively and many key turns, so I went inside then back 20 minutes later and it would not crank again.

Everything on the car works. It just wont crank when I turn the key. I have 2 keys and neither work.
Ive tried both ignition switches. Checked the battery, it is good and fairly new, tried jumping the battery. Checked the starter motor and it is getting 12v. Checked the fuses and they're good. I took the CLU from under the seat and it is good and dry. The fuse on it is good, I am still able to lock and unlock remotely. I swapped the relays around in the back. That didn't work. My only breakthrough was yesterday when I got it to crank by bridging the Start Lock relay. Now if I bridge the relay the car cranks at least but still will not start.

Can anybody please give me advice on this that might have seen these symptoms before?

Thank you

Steve Tinker · 10-19-2016, 02:51 PM

I think you may have a faulty new ignition switch - why did you replace the old one?
But here's a couple of other possibilities...

1) There is a clutch interlock switch mounted close to the clutch pedal. Make sure it works or bridge it out temporarily and see if the car starts.

2) CPS (crank position sensor) often fails when hot. If your tach moves when the car is cranking, that's a good sign the CPS is faulty. Use the search function for lots of details.

3) What's the start lock relay? If you are bridging it, it could be faulty. Does the starter solenoid click when you turn the key? If you turn the headlights on, do they dim when you try to start the car - if they don't the starter motor is not pulling power & could be faulty.

4) Can you hear the fuel pump run for a couple of second when the ignition switch is first turned on?

Gelbster · 10-19-2016, 03:37 PM

"If your tach moves when the car is cranking, that's a good sign the CPS is faulty."
You my want to Edit to insert 'NOT' ?
If your tach moves when the car is cranking, that's a good sign the CPS isNOT faulty.

Steve Tinker · 10-19-2016, 10:29 PM

Quote:

Originally Posted by Gelbster

"If your tach moves when the car is cranking, that's a good sign the CPS is faulty."
You my want to Edit to insert 'NOT' ?
If your tach moves when the car is cranking, that's a good sign the CPS isNOT faulty.

Ahhh - Altzheimer brain fade once again, sorry for the confusion.

particlewave · 10-19-2016, 04:46 PM

Possibly clutch switch bad or you aren't pushing it in all the way. This has gotten us all at some point.

pastey123 · 10-19-2016, 07:10 PM

Thank you everyone for replying. I should have mentioned that the clutch switch works fine. I was getting the car to crank and the clutch switch prevents you from cranking the engine.

Yesterday I ordered the Autel MD802 from amazon and received it today. Scanning the system revealed that the car was not recognizing the keys. I cleared these fault codes and the car word fine now.

Now the real question is why did this happen? What can cause the car to stop recognizing the key seemingly out of nowhere?

particlewave · 10-19-2016, 10:44 PM

Quote:

Originally Posted by pastey123

I was getting the car to crank and the clutch switch prevents you from cranking the engine.

Then why did you say 4 times in your first post that it wouldn't crank?

Glad you are getting somewhere.

pastey123 · 10-19-2016, 11:57 PM

Quote:

Originally Posted by particlewave

Then why did you say 4 times in your first post that it wouldn't crank?

Glad you are getting somewhere.

Let me clarify. The car would not crank at all until I tried bridging the start lock relay. With the relay bridged it began to crank but not start because the ignition was not recognizing the key. Since it was cranking I eliminated the possibility that it was the clutch switch at that point.

But the car runs now. I was able to remove the fault that was preventing the car from starting as shown in the picture.

I just would like to know what would cause the car to stop recognizing the key if anyone knows.

particlewave · 10-20-2016, 12:13 AM

No, I got that.

By bridging the start lock relay, you bypassed the clutch switch, so it was not eliminated as a culprit.

My guess is that you disturbed the transponder coil near the ignition switch. Possibly an intermittent connection on the coil that was disturbed or it moved and the keys pill wasn't close enough.
FWIW, I've had those same codes stored and it never caused a starting issue. I noticed them when I first got my Durametric. They may have been from long ago...no way to tell.

Edit: the coil is right behind the rubber bezel around the ignition. Remove the rubber and you'll be able to see it. I doubt it could have moved, but it's possible that the connector may be loose or something.