After disconnecting and re-connecting the battery

[Hilux2400]

I am fairly new (2 months 2003 Carrera 2) to 911/996 ownership. I have yet to disconnect the battery on my Porsche, but will need to do so at some time. Also, it is likely that I will do a few repairs over the coming years and will need to reset a few things such as throttle body, window regulator and perhaps the tiptronic after a limp mode episode.

I have seen a number of posts about various re-set methods on these electrical items involving turning on the ignition for a minute, then turning off and then starting normally.

Is there a post somewhere that will give me guidance on these various re-sets?

Thanks

H

[darrinsmith]

Hi Hilux2400

Disconnecting or changing the battery on 996's should not mess anything up.

The only thing you really need to reset is the windows.

You just wind the window all the way up and then hold the switch for 4-5 seconds to re-set the upper limit. It's actually in the owner's manual from memory.

Also if you have a PCM you'll need to let the car "equilibrate" in open sky for 10-15 minutes. Again this is also in the manual.

If your transmission is going into limp home then you may have a bigger problem. In that case you should get the durametric software.

It'll only take one job to pay for itself.

Cheers from Oz

DS

[Hilux2400]

Thanks Darrin

I know about the window re-set in the manual. However, I have seen somewhere a post that gives lots of info on various re-sets and I just can't find it.

Regards

H

[wross996TT]

With all DME systems, the engine must run for several minutes before the engine control module can

relearn the idle speed and mixture adaptation values! After the battery is connected.

With the DME ME 7.8, it is necessary to carry out a learning and adaptation routine as described below:

1. Switch the ignition on for 1minute without starting the

engine. Do not actuate accelerator pedal.

2. Switch off ignition for at least 10 seconds.

The limit positions of the power windows are deleted from the control module when the battery is disconnected and

connected.

Manually close each power window as far as it will go, then press the rocker switch for closing the window again.

The limit position of the respective power window is now stored in the control module again.

In the case of vehicles with PCM, the date and time are deleted when the battery is disconnected!

The time is deleted when the power supply is disconnected. Enter the current time again. (Or see below)

If the power supply is interrupted by a discharged or

disconnected battery with the tank containing less than 19 l, the calculated value for the range on remaining fuel in the

instrument cluster will be incorrect or deleted.

If the tank contains less than 19 l, it is possible that the fuel level warning light is no longer activated.

If the power supply is restored with the fuel level at less than 19l, it is possible that the fuel level

display may subsequently display an incorrect value.

Fill the tank; then the fuel level sensor is in operating range and its display precision is guaranteed

The PCM reverts to the Code input function when the battery is disconnected and is thus no longer

ready for operation.

When the power supply is disconnected, the built−in GPS receiver loses the so−called almanac

containing the satellite orbital paths.

The date and time are deleted when the battery is disconnected.

Radio stations stored by the customer are no longer displayed.

If the telephone card was inserted and the telephone was ready for

operation, the telephone is subsequently disabled.

1. Input the PCM code. If the code card is unavailable, the PCM code can also be read from the DME

control module (under "Vehicle data").

2. It is also possible to gain this code from the Porsche IPAS.

3. Switch on the PCM with a free panoramic view for approx. 20 minutes (to load GPS

almanac).

4. The date and time are also adopted once the GPS almanac has been loaded; it may be necessary to

change over to summer time (daylight−saving time). This time is transferred to the instrument cluster. If the

time is then manually changed by means of the instrument cluster, this time is adopted by the PCM and

synchronised with GPS time.

5. The stored stations are displayed again when station buttons 1 to 6 are pressed.

6. The telephone is enabled again when the telephone PIN code is entered with the SIM

telephone card inserted

[Richard Hamilton]

There are a couple of provisos when resetting adaption vales on ME7.2 and 7.8:

[Hilux2400]

Thank you all - that's great advice.

I have read the tutorial on throttle body cleaning and I am apprehensive about moving the butterfly manually in case I damage the throttle body stepper motor. Is it OK to move it manually, providing the ignition is off?

I have also been looking at plug changes and the conclusion I have come to is that the easiest path is to take off the silencers. From what I can see on the car, and from what I have read, silencer removal is pretty straightforward. There is always the chance that when removing the three nuts from the silencer studs that the studs might shear off. However, new studs can easily be welded back on in replacement.

Are there detachable sparking plug sleeves, sealed with "O" rings, on the 996 2003 3.6litre models?

H

[Loren]

Thank you all - that's great advice.

I have read the tutorial on throttle body cleaning and I am apprehensive about moving the butterfly manually in case I damage the throttle body stepper motor. Is it OK to move it manually, providing the ignition is off?

I have also been looking at plug changes and the conclusion I have come to is that the easiest path is to take off the silencers. From what I can see on the car, and from what I have read, silencer removal is pretty straightforward. There is always the chance that when removing the three nuts from the silencer studs that the studs might shear off. However, new studs can easily be welded back on in replacement.

Are there detachable sparking plug sleeves, sealed with "O" rings, on the 996 2003 3.6litre models?

H

No, the 3.6 liter has different spark plug tubes (metal) that do not leak.

[Hilux2400]

Thanks Loren

[bcrdukes]

Sorry to steal the thread, but did a search and this thread popped up.

When changing/replacing the battery, will the radio require a code when the new battery is installed? The previous owner lost the radio card and factory manuals during a cross-country move. I want to be sure it will not affect anything when I replace the battery, which I have reason to believe is 5+ years old.

Edit: Mine is a MY04 996 with Bose system and Becker CDR-22/23?

Edited April 20, 2014 by bcrdukes

[JFP in PA]

Sorry to steal the thread, but did a search and this thread popped up.

When changing/replacing the battery, will the radio require a code when the new battery is installed? The previous owner lost the radio card and factory manuals during a cross-country move. I want to be sure it will not affect anything when I replace the battery, which I have reason to believe is 5+ years old.

Edit: Mine is a MY04 996 with Bose system and Becker CDR-22/23?

There is a specific thread on this forum about lost radio codes and how to retrieve them, suggest you repost there.....................

[bcrdukes]

Ah, thanks for that, JFP in PA!

I just verified - I have the CDR-23. :)

[Loren]

Ah, thanks for that, JFP in PA!

I just verified - I have the CDR-23. :)

From the Lost Radio Code FAQ...

"CDR-23 (or later):

These radios do not have a security code - that is, not that the user enters.

These radios are security tested on the MOST (fiber optic bus) system to see if they are the "programmed" radio. The radios are programmed and recognized by the car?s DME and can only be replaced by a shop with a PST2 orPIWIS. These radios will not request a code when battery power is disconnected."

[Hilux2400]

Before I take the battery out of my 996 I connect a fused backup 12v supply to the jump start points in the engine compartment. It saves having to worry about re-setting anything when the main battery is replaced.

H

[xmac]

I've had an issue after disconnecting my battery where the mileage on the car in the odometer displayed either 599,999 or 999,999 miles after reconnecting the battery. This is the procedure I used to get it back to normal:

Put the key in the ignition.

Disconnect the battery negative cable.

Turn the key to position 1.

Then turn the key to the off position, leave key inserted.

Then hook up the battery cable and tighten properly.

Turn the key to position 1 and the display should be back to normal.

You may have to twist on the instrument cluster knob to change units.

To switch between km and miles, if display is in km:

With the ignition on, hold the instrument cluster button (clock looking button on the left ) turned to the left for about 5 seconds.