Lost power - will NOT turn-over

[LemmyCaution]

On the way home tonight, 1.5 miles from home, my 1999 Boxster lost power. Electrical power is ample but the car will NOT turn over. No drama with the engine - I coasted in gear, no odd noises (except lack of noise), no spilt fluids, high temps or strange smells. No CELS. In fact CEL does NOT light when ignition is on.

While waiting for AAA, I connected my laptop and fired up Durametric software. It does not see the ECU - what aside from an ECU failure could it be? While waiting, I did some searches for 'lost power' at Renntech.org (with my trusty ATT card) and found tons of posts about lost radio codes.

Any ideas? Ignition Switch? ECU? Relay? Fuse? The fuel pump fuse is okay - checked that but that would not explain why it will not turn over. Now that it's home, tried spare key to no avail. Bypassed the clutch microswitch - no love there either.

Need help troubleshooting before I tow it off to Dutch Treat - .

Thanks

Edited October 31, 2008 by LemmyCaution

[LemmyCaution]

On the way home tonight, 1.5 miles from home, my 1999 Boxster lost power. Electrical power is ample but the car will NOT turn over. No drama with the engine - I coasted in gear, no odd noises (except lack of noise), no spilt fluids, high temps or strange smells. No CELS. In fact CEL does NOT light when ignition is on.

While waiting for AAA, I connected my laptop and fired up Durametric software. It does not see the ECU - what aside from an ECU failure could it be? While waiting, I did some searches for 'lost power' at Renntech.org (with my trusty ATT card) and found tons of posts about lost radio codes.

Any ideas? Ignition Switch? ECU? Relay? Fuse? The fuel pump fuse is okay - checked that but that would not explain why it will not turn over. Now that it's home, tried spare key to no avail. Bypassed the clutch microswitch - no love there either.

Need help troubleshooting before I tow it off to Dutch Treat - .

Thanks

[LemmyCaution]

Thanks to the luck of the British and the Grace of God - Problem resolved - fuse B8 - 15A supplies ECU/Alarm system. One telltale was that when I unlocked the car with the key, the doors relocked upon inserting key in ignition accompanied with great fanfare from the seatbelt alarm (ding/dong).

Now to find out why the fuse blew? Age?

I'll pull the seat and have a close look at the alarm box. There is only one 'water incident' of significance - a blocked passenger side drain a few years ago but it was very minor dampening a very small area on that side of the car.

UPDATE at 11am. Drove the car - fuse blew again within a couple of blocks. I replaced it with a 25 amp and drove it to my garage where it is now parked. Waiting til I can find time to look further - ideas or similar experience from anyone?

Edited October 31, 2008 by LemmyCaution

[IFlyS5]

Sounds like the immobilizer to me. Can't imagine what would trigger that while driving though.

Good luck!

[LemmyCaution]

Sounds like the immobilizer to me. Can't imagine what would trigger that while driving though.

Good luck!

Ok - based on everything I'd read - the M535 control box (imobilizer) seemed to be the culprit though in 9 years I was not aware of the area under the front seat ever being wet. I disconnected the battery, pulled the seat, vacuumed and cleaned the entire area which appeared to be very dry.

Then, I opened the M535 box - it couldn't have been cleaner and drier than when it was pulled from a parts bin in Uusikaupunki in April 99.

Several weeks ago, I had a P0410 and a P1411 CEL which I believe was caused by a vacuum leak. I went through the engine and retraced my steps. I noticed that the electronic side of the PSE system had fallen off its mount. When I fished it back out of the engine compartment, I found the cause of the short. The wires connecting the valve to the PSE had come into contact with the exhaust and a good 1.5 inches of insulation had melted which led to a short with the exhaust or whatever the valve was nearest to.

This morning, I repaired the harness and secured the valve to a more solid mounting place. So far, so good - no blown fuse - it apparently failed at either 45 or 5 mph - the times at which the valve is activated.

Edited November 1, 2008 by LemmyCaution

[juniinc]

is your alarm sys working properly?

no double beep ? horn is going off when the alarm is triggered?

[LemmyCaution]

is your alarm sys working properly?

no double beep ? horn is going off when the alarm is triggered?

Maybe I wasn't clear :D

I traced the problem to a valve for original Porsche Sports Exhaust that was causing a short.

The alarm system was not the culprit.

Car runs better than ever - earlier in the year I installed a new generation PSE but didn't install the electronics. I will install the new electronics including dash switch AND a master switch for the system over Thanksgiving.