Jump to content

Welcome to RennTech.org Community, Guest

There are many great features available to you once you register at RennTech.org
You are free to view posts here, but you must log in to reply to existing posts, or to start your own new topic. Like most online communities, there are costs involved to maintain a site like this - so we encourage our members to donate. All donations go to the costs operating and maintaining this site. We prefer that guests take part in our community and we offer a lot in return to those willing to join our corner of the Porsche world. This site is 99 percent member supported (less than 1 percent comes from advertising) - so please consider an annual donation to keep this site running.

Here are some of the features available - once you register at RennTech.org

  • View Classified Ads
  • DIY Tutorials
  • Porsche TSB Listings (limited)
  • VIN Decoder
  • Special Offers
  • OBD II P-Codes
  • Paint Codes
  • Registry
  • Videos System
  • View Reviews
  • and get rid of this welcome message

It takes just a few minutes to register, and it's FREE

Contributing Members also get these additional benefits:
(you become a Contributing Member by donating money to the operation of this site)

  • No ads - advertisements are removed
  • Access the Contributors Only Forum
  • Contributing Members Only Downloads
  • Send attachments with PMs
  • All image/file storage limits are substantially increased for all Contributing Members
  • Option Codes Lookup
  • VIN Option Lookups (limited)

Recommended Posts

So, when it rains it pours I guess.

2004 CTT.

Wife and I took the kids to school this morning. On the highway there would be what felt like a miss every few seconds. After a couple miles of this, the PSM Workshop Failure popped and the "miss" stopped. We got off at the exit for school and while waiting at the stop, wife remarked that the steering was really stiff, then a second later it shutoff. Put it in park and restarted. The PSM and check engine lights were on. Dropped off the kids and went home...didnt push it, but despite the warning lights everything seemed normal.

Got home and scanned it:

7 DME faults - key immobilizer, O2 sensors, MAF, TB, DVE.  Codes in attached pics.

1 Transmission Fault - DME 1314

1 PSM fault - DME 1314

From some research it sounds like the first thing I should check is the health of the battery/alternator, correct?

post-94939-0-04786000-1462983410_thumb.j

post-94939-0-61864500-1462983543_thumb.j

post-94939-0-41930600-1462983557_thumb.j

Edited by 5thlilpiggy
Link to comment
Share on other sites

  • Moderators

Low battery/alternator voltages can cause the car to illuminate MIL lights, but usually does not make it throw codes.  While checking both is a good idea, I would also suggest getting the full list of codes as well.

Link to comment
Share on other sites

Low battery/alternator voltages can cause the car to illuminate MIL lights, but usually does not make it throw codes.  While checking both is a good idea, I would also suggest getting the full list of codes as well.

 

Edited post with codes.

 

If it helps, vehicle currently has 156k miles, we've owned it for about 2 years and 35k miles.  I changed the plugs in the fall (~8k miles ago) and the battery was replaced by the PO about 2.5-3 years ago.  He also had some corrosion in wires/splices repaired under the drivers seat because he couldnt get it out of park one day.

Edited by 5thlilpiggy
Link to comment
Share on other sites

Once again, I'm an idiot. I need to not work on this when I'm stressed out about other things I think.

I dont know if it's a cause these codes but I didn't put the clamps back on the rubber intake hoses  :huh:

 

Went for a short drive.  Got up to 60, punched it off a rolling stop, no funny behavior.

Edited by 5thlilpiggy
Link to comment
Share on other sites

Everyone makes mistakes.........glad you got it sorted. :thumbup:

 

Hope so...wife went 20 miles to work with no issues.

 

Why would loose intake hoses cause the DME to transmission/PSM communication issues and give a key immobilizer error?

 

Did the throttle go crazy adjusting to the scenario and the system just threw its hands in the air and gave up?

Edited by 5thlilpiggy
Link to comment
Share on other sites

  • Moderators

 

Everyone makes mistakes.........glad you got it sorted. :thumbup:

 

Hope so...wife went 20 miles to work with no issues.

 

Why would loose intake hoses cause the DME to transmission/PSM communication issues and give a key immobilizer error?

 

Did the throttle go crazy adjusting to the scenario and the system just threw its hands in the air and gave up?

 

 

The short answer is that they shouldn't be able to do that.  The loose connectors should have allowed air into the intake after the MAF, which should confuse the Hell out of the DME and cause it to try to adjust the air fuel ratio to compensate, which is totally unrelated or connected to the transmission or PSM system.

Link to comment
Share on other sites

  • 2 weeks later...

The PSM Workshop Failure followed by a stall out happened again.

 

PSM popped about 3 miles from home.  On the section of highway for my exit I noticed I was getting no throttle response...looked at the tach and the rpms were at 0, so I pulled off.  Restarted and the idle was hunting from 300-1200, but I was pretty close to home and was able to kinda limp back.  

 

Pulled the following codes (the CEL was NOT on):

 

P2138 Throttle/Pedal Position Sensor/Switch "D" / "E" Voltage Correlation

P2126 Throttle/Pedal Position Sensor 'E' circuit range/performance

P2121 Throttle/Pedal Position Sensor 'D' circuit range/performance

 

Transmission Fault - DME 1314

PSM fault - DME 1314

 

After I read the codes, I went for a short drive around the block and everything appeared normal.

 

Should I start with the battery?  As I said mine is going on 3 years old, and Advance Auto has 30% off so I can get one for $110 today.

 

If it helps, I can read live data from the modules as well as the DME.

 

Maybe of note: When warm weather hits, I get air suspension warnings. It goes all winter just fine, but once we hit 70* weather it pops.  I replaced the compressor ring last month, because that certainly seemed to be piston seal related, but the warning persists (or maybe this is coincidentally something different).  I noticed it pops whenever hit 80mph and it tries to lower.  The code is 1400.  I was going to look into the valves etc. today, but then this PSM deal happened again and am wondering if it is battery related...

Edited by 5thlilpiggy
Link to comment
Share on other sites

  • Moderators

The PSM Workshop Failure followed by a stall out happened again.

 

PSM popped about 3 miles from home.  On the section of highway for my exit I noticed I was getting no throttle response...looked at the tach and the rpms were at 0, so I pulled off.  Restarted and the idle was hunting from 300-1200, but I was pretty close to home and was able to kinda limp back.  

 

Pulled the following codes (the CEL was NOT on):

 

P2138 Throttle/Pedal Position Sensor/Switch "D" / "E" Voltage Correlation

P2126 Throttle/Pedal Position Sensor 'E' circuit range/performance

P2121 Throttle/Pedal Position Sensor 'D' circuit range/performance

 

Transmission Fault - DME 1314

PSM fault - DME 1314

 

After I read the codes, I went for a short drive around the block and everything appeared normal.

 

Should I start with the battery?  As I said mine is going on 3 years old, and Advance Auto has 30% off so I can get one for $110 today.

 

If it helps, I can read live data from the modules as well as the DME.

 

Maybe of note: When warm weather hits, I get air suspension warnings. It goes all winter just fine, but once we hit 70* weather it pops.  I replaced the compressor ring last month, because that certainly seemed to be piston seal related, but the warning persists (or maybe this is coincidentally something different).  I noticed it pops whenever hit 80mph and it tries to lower.  The code is 1400.  I was going to look into the valves etc. today, but then this PSM deal happened again and am wondering if it is battery related...

 

I would note the codes, and clear them, then test the car again.  If the same codes come back I'd start with the throttle position sensor system, which seems to be the source of many of the codes, but I would load test the battery and check the alternator voltage as well.

Link to comment
Share on other sites

 

I would note the codes, and clear them, then test the car again.  If the same codes come back I'd start with the throttle position sensor system, which seems to be the source of many of the codes, but I would load test the battery and check the alternator voltage as well.

 

 

I dont know how accurate the DME live data feed voltage is, but I had 12v at rest, 9.5V when starting the car, and 13.6-13.9 running.

Edited by 5thlilpiggy
Link to comment
Share on other sites

  • Moderators

 

 

I would note the codes, and clear them, then test the car again.  If the same codes come back I'd start with the throttle position sensor system, which seems to be the source of many of the codes, but I would load test the battery and check the alternator voltage as well.

 

 

I dont know how accurate the DME live data feed voltage is, but I had 12v at rest, 9.5V when starting the car, and 13.6-13.9 running.

 

 

Voltage is slightly low, normal range is 13.5-14.5V.  I would load test both the battery and alternator.

Link to comment
Share on other sites

Reminds me to my constant problems with my CS. The dealer changed parts like hell. Sensors, MAF, throttle body, etc. hundreds if not thousands. In the end i believe it is just a low voltage problem. As soon as i had new batteries the problems dissapeared.

Link to comment
Share on other sites

Reminds me to my constant problems with my CS. The dealer changed parts like hell. Sensors, MAF, throttle body, etc. hundreds if not thousands. In the end i believe it is just a low voltage problem. As soon as i had new batteries the problems dissapeared.

 

With my battery pushing 3 years and the battery from Advance Auto being such a good deal I just went and got it.  If the air suspension works properly again after install thats probably a good sign.

 

Voltage is slightly low, normal range is 13.5-14.5V.  I would load test both the battery and alternator.

 

I did the "turn everything on" alternator load test suggested in ekstroemtjs old thread.  Idling with headlights, rear defrost and A/C on, Im at 13.6v.  

 

My multimeter broke so I dont have the greatest capabilities at the moment.  The fact that the live data read 9.5v the first time I tested a startup would at least suggest the battery isnt great right?  If the new battery doesnt make an immediate difference (suspension) Ill get a meter and do some better testing.

 

Edited by 5thlilpiggy
Link to comment
Share on other sites

  • Moderators

 

Reminds me to my constant problems with my CS. The dealer changed parts like hell. Sensors, MAF, throttle body, etc. hundreds if not thousands. In the end i believe it is just a low voltage problem. As soon as i had new batteries the problems dissapeared.

 

With my battery pushing 3 years and the battery from Advance Auto being such a good deal I just went and got it.  If the air suspension works properly again after install thats probably a good sign.

 

Voltage is slightly low, normal range is 13.5-14.5V.  I would load test both the battery and alternator.

 

I did the "turn everything on" alternator load test suggested in ekstroemtjs old thread.  Idling with headlights, rear defrost and A/C on, Im at 13.6v.  

 

My multimeter broke so I dont have the greatest capabilities at the moment.  The fact that the live data read 9.5v the first time I tested a startup would at least suggest the battery isnt great right?  If the new battery doesnt make an immediate difference (suspension) Ill get a meter and do some better testing.

 

 

 

Could be, but I would not be swapping out anything with out testing first.  The correct way to test a battery and alternator is with a load testing device, which puts extreme loading on each while also monitoring how each responds.  The devices themselves are not particularly expensive, and many auto parts stores now have them available for customers to use for free.  This is the one we use in the shop, very quick and accurate testing, and it cost about $75:

 

61x7NBvHnrL._SL1072_.jpg

Link to comment
Share on other sites

This is the one we use in the shop, very quick and accurate testing, and it cost about $75:

This one says its good for 125 amps and I can pick it up tomorrow in store: http://www.northerntool.com/shop/tools/product_200611634_200611634

 

Google isnt turning up much for testing the alternator with a load tester (it is all multimeter)...how do you do it?

Link to comment
Share on other sites

  • Moderators

 

This is the one we use in the shop, very quick and accurate testing, and it cost about $75:

This one says its good for 125 amps and I can pick it up tomorrow in store: http://www.northerntool.com/shop/tools/product_200611634_200611634

 

Google isnt turning up much for testing the alternator with a load tester (it is all multimeter)...how do you do it?

 

 

Instructions should come with the unit, but this is the basics: http://www.delcoremy.com/MediaLibraries/DelcoRemy/DelcoRemy/Literature/Troubleshooting/Delco-Remy-Charging-Troubleshooting-Guide-8-13.pdf

  • Upvote 1
Link to comment
Share on other sites

  • Moderators

 

 

Thanks!

 

Can testing be done at the jumper terminals by the brake fluid?

 

 

No, it has to be done at the battery terminals.

Link to comment
Share on other sites

  • Moderators

 

 

 

No, it has to be done at the battery terminals.

 

 

Does the alternator test need to be done at the alternator terminals?  That sounds dicey...

 

 

Clamps on the battery, but with an amp meter clamped on the positive alternator lead to read amperage draw, which shows how the unit is responding to the load on the battery.  Again, many auto parts stores have this setup for free use by customers, so check you local before buying the hardware.

Link to comment
Share on other sites

Clamps on the battery, but with an amp meter clamped on the positive alternator lead to read amperage draw, which shows how the unit is responding to the load on the battery. Again, many auto parts stores have this setup for free use by customers, so check you local before buying the hardware.

Wait, so I need to tear in and get alternator access to test the alternator?

 

 

 

 

Edited by 5thlilpiggy
Link to comment
Share on other sites

  • Moderators

 

Clamps on the battery, but with an amp meter clamped on the positive alternator lead to read amperage draw, which shows how the unit is responding to the load on the battery. Again, many auto parts stores have this setup for free use by customers, so check you local before buying the hardware.

Wait, so I need to tear in and get alternator access to test the alternator?

 

 

Yes, you need to access the primary wire on the alternator.

Link to comment
Share on other sites

Yes, you need to access the primary wire on the alternator.

Do you mean I just need to put an amp meter on #40 or #41 or actually tear the airbox, etc. out and get it directly on the alternator?

post-94939-0-19193200-1463948037_thumb.j

Edited by 5thlilpiggy
Link to comment
Share on other sites

  • Moderators

To fully test the system, you need access to:

 

  1. Both the positive and negative battery terminals (for load test device heavy cables).
  2. The terminal lug on the back of the alternator where the primary wire attaches (for checking diode ripple).
  3. The alternator primary wire itself (for an amp meter to clamp around and measure current draw).

If this is outside your level of comfort, I'd suggest taking it to a shop to have it tested.

Link to comment
Share on other sites

To fully test the system, you need access to:

  • The terminal lug on the back of the alternator where the primary wire attaches (for checking diode ripple).
  • The alternator primary wire itself (for an amp meter to clamp around and measure current draw).
If this is outside your level of comfort, I'd suggest taking it to a shop to have it tested.

 

Not so much the comfort level, but maybe Im not understanding the simplicity of access  :huh:

 

Can I get to the terminal and primary wire just by removing the tire and wheel well liner?  If not, and you have to go through the first parts of the alternator removal process, I dont see how you could do that, hook everything up, and still have the engine run.

 

 

Edit: Im sure your way is much more thorough and appropriate, so dont think this is a counter argument :cheers:   I just read the instructions that came with the load tester.  It says to just hook up to the battery terminals and when you rev to 12-1500rpm it will run a charging system draw to test the alternator.  

Edited by 5thlilpiggy
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.