[flash]

Reading Porsche 968 Fault Code with Check-Engine Lamp (not for R.O.W. cars)



Basic Procedure:

1. Verify operation of Check-Engine lamp. (Lamp should light up when ignition is switched on)



2. Fault codes on USA vehicles may be read using the Check-Engine lamp. To trigger the flashing code, fully depress the accelerator pedal for 3 seconds with the engine off and the ignition on until the Check-Engine lamp flashes. Then ease off the throttle.



3. Light will repeatedly flash stored code sequence(s) until ignition is turned off.



Known Limitations:

Diagnostics of this nature are typically performed by professionals with access to specialized tools. The Bosch Hammer/System Tester 9288 (or one of it's successors) is the preferred way to read fault codes and will be required to erase the fault memory. Also, the fault codes listed are intended to serve as a starting point for follow-on diagnostic efforts and, thus, knowing the fault code is not necessarily the same as knowing which component is faulty.



NOTE: A "2" IN THE SECOND DIGIT LOCATION OF THE 4 DIGIT CODE INDICATES AN "INTERMITTENT" ISSUE



Fault Codes (968): (Flashing Code Fault Description)

1-5 No Fault

1-1-1-1 Supply voltage

1-1-1-4 Engine temperature sensor 2

1-1-1-6 Throttle potentiometer

1-1-1-7 Oil temperature sensor

1-1-1-8 Rpm signal

1-1-1-9 Speed signal - Speedometer

1-1-2-1 Air flow sensor

1-1-2-3 Oxygen regulation

1-1-2-4 Oxygen sensor

1-1-2-6 Ignition timing change

1-1-2-7 Open winding of idle stabilizer

1-1-2-8 Close winding of idle stabilizer

1-1-2-9 Activation of AC relay

1-1-3-1 Knock sensor 1

1-1-3-2 Knock sensor 2

1-1-3-3 Control unit faulty

1-1-3-4 Hall signal

1-1-3-5 VarioCam

1-1-3-6 Idle CO potentiometer

1-1-4-1 Control unit faulty

1-1-4-2 Fuel pump relay (DME-relay)

1-1-4-3 Tank ventilation relay

1-1-4-5 Check Engine warning lamp

1-1-5-1 Injection valve cylinder 1

1-1-5-2 Injection valve cylinder 2

1-1-5-3 Injection valve cylinder 3

1-1-5-4 Injection valve cylinder 4



*Second number in sequence may vary (1 is for a constant fault. 2 is for a loose contact)

Partial Post: Please Login or Register to read the full post.

[rhudeboye]

Ctrl + P



Thanks Bob

Partial Post: Please Login or Register to read the full post.

[968Syncro]

Thanks Flash. Very valuable! Printed and in my owners manual / glove box. I get the feeling I'll want this someday when on the road.



Roland

Partial Post: Please Login or Register to read the full post.

[Kim]

Just note that I think that this doesn't work on Canadian cars. I don't think that we have a CEL.

Partial Post: Please Login or Register to read the full post.

[flash]

thanks - not sure about that but note made about ROW above

Partial Post: Please Login or Register to read the full post.

[Dano]

Tried to do this on mine but it doesn't seem to work. Does there have to be a fault first; for it to dump codes?

Partial Post: Please Login or Register to read the full post.

[flash]

no - does your "!" light come on when you start the car?

Partial Post: Please Login or Register to read the full post.

[Rwinter]

I'm having a little trouble understanding how to translate the blinks to the code sequences. Mine flashes 5 times at about a 1 second interval and then pauses for about 2 seconds, then the light stays on for 3-4 seconds, off for about 2 seconds and then blinks for 1 second. I thought those would translate to 1-1-1-1-1 (but codes are only 4 digits) and 4-0-0-1 (but I do not see any codes starting with 4).



Any help would be appreciated.



-Rob

Partial Post: Please Login or Register to read the full post.

[Kim]

you have to count the blinks. For example, mine recently (still has) the 1-2-3-5 code. so the light blinks once, stops, blinks twice closely together, stops, blinks three times closely together, stops, then 5 times. Five in a row right from the start after one blink is no fault. You will get something. Sort of like Morse code.

Partial Post: Please Login or Register to read the full post.

[Jamie '92 968]

Hey Flash!
Thanks for the codes! (and for directing me to this forum)

I found a procedure that had a couple of additional details, and a few observations from my "blink test" that I did recently at your suggestion.
Thought somebody might find this useful someday....

First, I read that you can clear the faults by turning the ignition to ON and then holding down the accelerator for 11 seconds.
Since I didn't have any faults displayed, I couldn't verify this.

When I did the test, I noticed that after the blinks call out the numbers, the last blink was longer than the rest. It appeared that this long blink indicated the end of the sequence.
In other words, my patern was 1 short blink, followed by a pause, followed by 5 short blinks, followed by a pause, followed by a long blink, followed by a repeat of the whole sequence.
Since the sequence just repeats over and over, it is difficult to tell where it starts and stops. I think the long blink is the key.

The procedure I read says that after you read a code, you should press the accelerator back down again for about 3 seconds to get to the next code.
When I did this, the check engine light was constantly on while I pressed the accelerator, and then I released it when it started flashing to read the next code.

Lastly, the procedure I have said that a code of one blink (followed by a long blink) indicated that all codes had been displayed.

Partial Post: Please Login or Register to read the full post.

[flash]

happy to help

yes, that long blink is the break between sequences

nice addition of information to the test - that is EXACTLY the kind of stuff that this site is about - thank you very much

welcome welcome

Partial Post: Please Login or Register to read the full post.

[Kim]

i have the original 1991 Porsche document on all of this (33 pages) in pdf format if anyone wants it.

Partial Post: Please Login or Register to read the full post.

[flash]

please send it to me

Partial Post: Please Login or Register to read the full post.

[968Z]

Jamie, Thanks for the tip on clearing the codes....and welcome aboard!

Partial Post: Please Login or Register to read the full post.

[Kim]

Flash - it is 2.3 Mb. Not sure where to send it and don't seem to be able to figure out how to attach to any post. Ideas?

Partial Post: Please Login or Register to read the full post.

[flash]

got the file - thanks - i have to look into the copyright issues - that file is straight from the workshop manual - we don't want to get into trouble

it may be too big for the current settings too, so i have to look at that as well

Partial Post: Please Login or Register to read the full post.

[Bruckner]

Just note that I think that this doesn't work on Canadian cars. I don't think that we have a CEL.

My canadian 92 had no light bulb in the CEL socket, I put one in and the CEL appears to operate normally (lights up briefly on startup), and doing the blink test returns a 1-5 code leading me to believe ROW cars can run the test by simply pulling the instrument cluster (not all the way out, steering wheel stays on) and plugging the correct bulb/socket.

Partial Post: Please Login or Register to read the full post.

[Waylander]

No wire to the K line in the socket on row cars

Partial Post: Please Login or Register to read the full post.

[Bruckner]

No wire to the K line in the socket on row cars

 

What's the K line?

Partial Post: Please Login or Register to read the full post.

[Waylander]

The ECU has two data lines, the K and L

By connecting the k line through a bulb to earth you can enable the blink test on ROW cars

Partial Post: Please Login or Register to read the full post.