My "D" light blinks until the engine is warm

GSRP · 02-08-2007, 06:25 AM

Yesterday I took off in the early morning with out side temp about 37. For the second time, the "D" on my shift indicator began blinking until the engine reached normal operating temp. Then it stoped and I was able to use the Tiptronic mode. The transmission did not act funny or shift erratically at any time.

Any ideas about the possible cause? Also, once I put the car in Drive -- my backup lights came on! Strange.

The dealer spent about an hour testing and found no codes in the computer. He thinks I may need a new tranny switch -- a pricey item with installation!

Any thoughts would be appreciated.

-gene

By the way, this is on my 1999 Boxster with 12K on the factory rebuilt engine and 1K on the RMS.

AFJuvat · 02-09-2007, 06:13 AM

Tranny switch is bad - sorry.

AFJ

GSRP · 02-09-2007, 06:29 AM

Thanks for your post -- even though I too am sorry it's the switch.

Did you have a similar experience that makes you certain -- or was it based on the details of my experience?

-gene

AFJuvat · 02-09-2007, 07:38 AM

I've had one similar experience with strange behavior of the transmission lights.

There are very few adjustments to the transmission and switch. The flashing D light is an indicator that the transmission is following a limited program that is restricting transmission operation. Add the fact that your backup lights come on when you select drive tell me that the switch itself (which isn't very well made I'm sorry to say) is in the process of failing.

To rule out any other possibility completely, the car will have to be hooked up to a PST-2 or 3. Tech should monitor transmission temperature to ensure that the tiptronic module is getting the correct inputs.

Also, if the tiptronic module is swappable, they may want to swap it with a tester and see if the problem goes away before digging into the switch (I can't remember if the tip modules are swappable)

AFJ

GSRP · 02-09-2007, 07:41 AM

Excellent response -- thanks for the details -- at least I may sound a bit more knowledgeable talking with the tech!

-gene

tab tanner · 02-21-2007, 04:27 AM

Not to hilack, but I have a similar problem, The trans D light will flash and the car will drive very badly, if you park it and let it set for an hour or so you can start it up and it will drive fine. Very intermitent drives great most of the time and then like crap for no reason. Could this also be the switch? I have about 82K miles on it I for got to mention it's a 97'. I took it to the dealer they checked it out and found no problems so I drove it home, on the way I stoped for dinner ans the car did not make it out of the driveway. Towed it to the dealer and they said it need a transmission torque converter and an ECU?? I had it returned to my house. Got it the car and it drove perfectly?? Could the switch be the cause of this problem??
Thanks

GSRP · 02-21-2007, 05:03 AM

Tab,

I never had the problems you mentioned. My engine and transmission always performed flawlessly -- just that darn blinking "D" and next came the backup lights -- when I put the car in drive. It was a malfunctioning tranny switch -- it finally cost me $575 total. That was about $200 less than the dealer charged.

-gene

tab tanner · 02-21-2007, 04:01 PM

The engine always ran correctly just the trans would not upshift right, also it felt like the trans would go into netrual. I'm think ing the switch could be on it's way out??

smithmotorworks · 05-31-2007, 10:22 AM

We have an '03 that has the D and 4 Flashing. We are getting a code 10 with our PST2 but noone can tell us what it means.

Anyone here have any ideas?

AFJuvat · 06-01-2007, 04:46 AM

I will hit the books tonight - I have a copy of the tranny diagnostics manual.

smithmotorworks · 06-01-2007, 05:50 AM

That would be awesome. If you know where we might get a copy of the manual I would be interested in that also. We have alot of manuals in .pdf format we could also trade.