2003 Targa: No start, engine lid and front trunk won't open, car appears to have power

[Andrew911]

2003 Targa tiptronic. 60k miles

 

My past 24 hours of Porsche ownership have seen some highs and lows:

 

Yesterday, I replaced the driver's side door lock assembly to fix an issue where the glass was popping back up when the door was opened.  Took the car for a test drive and all was well.

 

Today, I took it to run errands.  Made several stops and each time it started and drove just fine, however, at one point the key fob button stopped locking the car, and I discovered that the passenger side was not locking when locking the car manually with the key (normal?).

 

I came home and it sat for a few hours.  Went to go for another drive, and now the car won't start.  Put the key in and turn, all the lights come on, radio, HVAC, etc, no start, not even a crank.

 

Thinking it was possibly a low battery, I tried to pop open the front trunk and engine lid.  Nothing.  It's like the buttons are dead.  Curiously, the button to pop the rear glass works fine, and I can open and shut it with no problems.

 

I tried the method of applying power via the red jumper in the driver's footwell with both my batter tender and a 12v Diehard jump pack.  Absolutely zero change.

 

Aside from the front trunk and engine lid, all electrics appear working, aside from interior lights.  Exterior lights are fine, I can adjust the driver's seat with controls and seat memory, turn on the radio, etc.

 

Any suggestion?  I am completely stumped, and quite frustrated.

Edited March 9, 2019 by Andrew911

[Ahsai]

What does the voltmeter in the cluster read when you turn the key to the last position before cranking? Fuses C1-C4 and E1 are good?

 

Also should check fuses for interior lights and door locks. Next suspect will be the ignition switch.

[Andrew911]

Thanks Ahsai, I'll check out your suggestions in the morning and report back.  I appreciate it very much!

 

If it is the ignition switch, would that cause the front trunk and rear engine lid from opening?

Edited March 9, 2019 by Andrew911

[Ahsai]

You're welcome. Please also check fuse B8 (alarm). Is the unit you put in a genuine Porsche door lock? I suspect it has something to do with the alarm system because the passenger lock, front lid and rear lid are all controlled by the alarm unit. The door lock assemblies are also fully connected to the alarm. I suspect somehow the alarm is armed so you can't start the car.

[Andrew911]

Yes, it is.  Bought it from the dealer, and it appeared identical in terms of dimensions and parts and such.  Colors were a bit different.  Original used a translucent cover while the new one was solid black.  Exact same part number.

[DBJoe996]

I agree.  It seems like an alarm system fault....key fob not working to unlock the car, engine lid and trunk lid releases locked down,  car not starting.  I know it might be a real pain in the neck, but you might consider putting the old door latch back on to see what happens.  Are you sure you got everything hooked back up right on the door latch?  BTW, did you disconnect the battery to remove the door panel?

[Andrew911]

Quick update:

 

-Fuses C1-C4, E1, and F8 all checked out from what I can tell

-Voltmeter reads 12v when key is turned, just under 14v when driving

 

Which leads me to the next part.  Today on a whim I tried to start the car and it fired right up.  Yesterday, it wouldn't do it no matter what, and today it started on the first crank.  Engine lid will open when key is in ignition and button pushed, but the horn beeps and interior lights flash when doing so (is that normal).  Front trunk still will not open with button on door sill or either key fob.

 

Agreed it looks like some kind of alarm module problem.  Would the next step be to somehow get the front trunk opened so I can disconnect the battery and hopefully reset it?

[DBJoe996]

The horn beeps and lights flashing is the alarm system telling you there is a alarm system zone fault somewhere.  Could be an open (or maybe in this case closed/locked when it should be open) zone.  Zones are: drivers/passenger doors, trunk lid, engine lid, glass (targa) top, gas cap lid, center console lid, and if you have it the glove box door. There are also two interior sensors in the overhead that detect motion when the car is locked.  I think getting to the battery and disconnecting is a good idea.  However, you have a problem since the trunk is not opening.  First thing to try is actually seeing if the trunk is already open.  Put your fingers under the trunk lid and try pulling up.  Second is to locate the emergency release cable under the passenger side headlight.  Unfortunately you need to pop the headlight out to make this a simple exercise, and  you can't do that without opening the trunk.  So you have to pull the  passenger wheel well liner and fish out the cable from behind.  Hopefully your wheel lock socket is not in your trunk!

Edited March 10, 2019 by DBJoe996

[Andrew911]

Thanks for the info, Joe.  The project had to be put on hold for a couple weeks but I am working on it again.

 

I managed to get the frunk open with the manual release cable.  It required quite a bit of effort to pull but it popped the lid.  Now the trunk won't close at all.  I can drop it and the latch will catch but it won't fully close, the lid pops back up.  Any ideas on that?

 

To clarify: the single beep of the alarm can be caused by the gas cap,  the fuel filler door latch, or both? 

 

Also, wanted to add: I left the negative battery cable off for about 30 minutes and got the same result: car fired right up with key, but no lock/unlock from the remotes.  Front trunk button like it's still dead, though engine and hatch glass buttons work fine.

Edited March 24, 2019 by Andrew911

[DBJoe996]

Not the gas cap but the fuel filler door.  Good that you managed to find the emergency release cable.  Now do yourself a huge favor and pull the plastic piece covering the hood latch and relocate the cable to just behind the front bumper tow hook plug.  It fits right in there and the next time all you have to do is pop the tow hook plug and there is the cable.

 

Now from your description of problems, I think you should take a look at the hood release actuator.  It might be the source of both problems, horn beep, stuck hood latch and it not working from the lock buttons.  See Part #19 here in this parts diagram.  I think you should be able to hear it click while someone operates the button.  If not, then it is probably faulty.

Lid Front

WWW.AUTOATLANTA.COM

---

 

 

[Andrew911]

Thanks again, Joe!  I take it part 99651112700 is what I need since it's for 2001 and newer?  Assuming 99762411900 is for 99-00 cars?

 

Would there be any advantage is replacing the entire lock mechanism?  

[DBJoe996]

Yes, you are correct on the actuator part number.  I don't see any advantage in replacing the entire lock mechanism unless it is corroded or stuck.  Usually some white lithium grease will help it operate freely.

[Andrew911]

Awesome, thanks.  Do you know if it's necessary to pull the front bumper to replace it?  A quick glance it didn't seem to be needed but a couple threads hint that it does.

[DBJoe996]

I am not 100% certain, but if you take off the plastic trim cover covering the hood latch, you should be able to see everything.  You pull the interior cover back a bit to reach the bolts that hold the hood latch to the frame.  It is all pretty straight forward from there.

[Andrew911]

Okay, cool, that's what it looked like to me as well.  Just making sure there weren't any gotchas lurking!  

[Andrew911]

Installed the new hood actuator, and no change.  Car starts up and runs, but nothing from key fobs, and front trunk switch inside the car does nothing.  It does light up though and I checked for any loose wires but found none.  Also did a check of fuses and still all looked good.

 

One thing I noticed is that the emergency release pull seems to trigger the hood actuator (is that normal operation?) so it seems to me like it should have power.

 

On the plus side I was able to get the hood to shut completely, though it still requires a pull of the emergency release cable.

 

I'm stumped.  Any other thoughts?  I have it on the battery tender wishing upon a star that maybe it just needs some juice.

 

Also, for anyone doing this in the future, or if Google brought you here,  the hood actuator is indeed very easy to install like Joe said.  No removal of the bumper cover required.  Get the hood popped open, undo the four caps that hold the plastic trim on, peel back the trunk liner, remove the two 10mm bolts, and then remove the actuator.  I found I had to peel back the foam to unclip the wiring harness.  The foam surrounding it wedges it in there pretty tight and it will seem like it's attached/glued, but it's not.  Just be careful you don't catch any wires.  

[DBJoe996]

Here's hoping a good charge on the battery helps.  Open the hood and  look up.  On either side is a rubber bumper and it is  adjustable.  You can twist them in and out to adjust the tension on the hood latch when the hood is closed.  Might  be they need to be turned in a tad to take some tension off the hood latch, and the actuator is pulling but not strong enough  to pop the hood.

 

Other than that, I would pull the electrical connector on the actuator and check it for both ground and voltage when the button is pushed.  Might also consider grounding the actuator and running a separate 12V supply wire to test it.

[Andrew911]

Just wanted to follow up and close the loop on this strange issue.  I ended up throwing in the towel and took it to my local shop.  There they diagnosed a cable to the alarm module was not plugged in correctly, which caused a lack of signal to the front trunk release, even though it had power.  Plugging in this cable correctly instantly got the front trunk working again.  They also found two frayed wires under the driver's seat and repaired those, though it was probably unrelated.  

 

During my troubleshooting, it appeared to me all the cables to the alarm module were nice and tight.  About the only thing I didn't do was pull the thing out entirely to check.  Maybe if I did I would have found the cable issue.  I'm not quite sure how a cable gets plugged in incorrectly but it's solved now.

 

One interesting tidbit.  I didn't know the horn itself was supposed to honk in the event something was left open when locking the car.  In my case, the interior lights would light up and a weak horn/squelch/chime sound was heard INSIDE the car.  Having only owned the car a few months and this being my first Porsche, I thought maybe this was normal.  When the car returned from the shop, the headlights flashed and the horn honked...i.e normal operation.  The shop diagnosed this cause as being a failed glovebox microswitch.  Sure as ****, when I pulled the glovebox I discovered the microswitch was indeed broken and the previous owner tried fixing it by wadding a bunch of electrical tape around it.  UGH!  To top things off, the little mount for the microswitch is missing, so a $2 part must now be shipped from Germany.  Dealer wasn't able to find any in the US.

 

Thanks to all who contributed to this thread, while we weren't able to solve the problem 100%, I learned a LOT about the car, item locations, what fuses do what, etc.  Invaluable knowledge for the future.

 

I also in turn was able to help out a fellow Renntech member in Germany with getting his front trunk open via the emergency cable.  So, I passed on some knowledge ?

 

Edited April 18, 2019 by Andrew911