997.1 C2S airbag fault 801B

[floatingkiwi]

Hi All

 

Got the above air bag fault the other day after a long drive.  It can be cleared by the durametric but turns on with the next ignition cycle, so it's permanent.

I did read about boxsters needing a new harness because of this, but my local porsche mech says it's probably the connection to the airbag in the door (inside the door panel) or the airbag itself, however I'd like to check the door harness connection point by the passenger's kick panel first, which is the easiest thing to do before I tear the door off - but not sure how to get in there yet.

RHD 2005 997.1 C2S in New zealand, so no salt and dry garages, no moisture issues etc.

[Loren]

Fault 801B 
Passenger's head airbag

Possible fault causes:
- Short circuit to B+/ground/between lines or open circuit in the lines

- Connection with other ignition circuit
- Passenger's head airbag faulty

- POSIP triggering unit faulty

[floatingkiwi]

Yes The local porsche guy says probably the air bag itself.

[floatingkiwi]

Well, I put a 3ohm resistor in place of the air bag and the light goes out and I can clear the code, so I guess the airbag needs to be replaced...

[floatingkiwi]

Loren - does a new (or second hand) airbag need to be coded to the car?  I have a durametric pro to clear codes etc.

[Loren]

7 hours ago, floatingkiwi said:

Loren - does a new (or second hand) airbag need to be coded to the car?  I have a durametric pro to clear codes etc.

 

No coding to the car - just clear the fault codes.

[floatingkiwi]

OK, reconnected the airbag and all is good.  So it was just the connection.

[asharma]

On 7/20/2019 at 1:08 AM, Loren said:

Fault 801B 
Passenger's head airbag

Possible fault causes:
- Short circuit to B+/ground/between lines or open circuit in the lines

- Connection with other ignition circuit
- Passenger's head airbag faulty

- POSIP triggering unit faulty

Hi, I was at my Porsche dealer yesterday and during my maintenance they noted the battery cable terminals were not secured to battery and the ground wire to ground cable was loose (nut was upside down). They secured  battery connections, Covered vehicle battery maintainer, Created Val, sent Val (I’m not sure what all that means...) anyway it now throws the airbag light with code 801b, which has to do with the passenger head airbag short circuit to B+ ...what would be the best way to debug? I’m not that technical but do have an Autel reader for Porsche...is there something simple I could just do at the battery level since that seems to be what was changed at the time? Thanks

Edited May 23, 2020 by asharma

[asharma]

13 hours ago, asharma said:

Hi, I was at my Porsche dealer yesterday and during my maintenance they noted the battery cable terminals were not secured to battery and the ground wire to ground cable was loose (nut was upside down). They secured  battery connections, Covered vehicle battery maintainer, Created Val, sent Val (I’m not sure what all that means...) anyway it now throws the airbag light with code 801b, which has to do with the passenger head airbag short circuit to B+ ...what would be the best way to debug? I’m not that technical but do have an Autel reader for Porsche...is there something simple I could just do at the battery level since that seems to be what was changed at the time? Thanks

Bump, any advice would be appreciated, thanks kindly

[JFP in PA]

23 minutes ago, asharma said:

Bump, any advice would be appreciated, thanks kindly

 

You need to d some electrical diagnostics using tools like a digital multimeter or a Power Probe to check the appropriate circuits for electrical faults.  A Porsche specific scan tool is required to check the POSIP system.  Extreme care is called for to prevent inadvertently tripping the system and inflating the air bag.

 

If you do not have access to the tools, or a complete understanding of how the air bag and igniter circuits function, take it to a professional as air bag systems are capable of severely injuring or even killing you.

[asharma]

33 minutes ago, JFP in PA said:

 

You need to d some electrical diagnostics using tools like a digital multimeter or a Power Probe to check the appropriate circuits for electrical faults.  A Porsche specific scan tool is required to check the POSIP system.  Extreme care is called for to prevent inadvertently tripping the system and inflating the air bag.

 

If you do not have access to the tools, or a complete understanding of how the air bag and igniter circuits function, take it to a professional as air bag systems are capable of severely injuring or even killing you.

Thanks for the warning, I SINCERELY appreciate it...I was “thinking” of simply removing the passenger side door panel to see if there was any obvious chaffing of wires etc...Does that sound like a safe plan or is there still risk of deployment? Thanks again

[JFP in PA]

2 hours ago, asharma said:

Thanks for the warning, I SINCERELY appreciate it...I was “thinking” of simply removing the passenger side door panel to see if there was any obvious chaffing of wires etc...Does that sound like a safe plan or is there still risk of deployment? Thanks again

 

I have very rarely seen side air bag wires chafe inside the door unless the window mechanism caught them and tore them up.  Usually, the problem is where the wire harness exits the door and enters the main body.  In any case, you need to be electrically testing the entire harness, not just looking for obvious damage.

 

You need to disconnect the battery and leave the car alone for at least thirty min.before doing any work.  I also prefer to work with a static discharge wrist strap on one arm any time I am working near or on the air bags.

[asharma]

27 minutes ago, JFP in PA said:

 

I have very rarely seen side air bag wires chafe inside the door unless the window mechanism caught them and tore them up.  Usually, the problem is where the wire harness exits the door and enters the main body.  In any case, you need to be electrically testing the entire harness, not just looking for obvious damage.

 

You need to disconnect the battery and leave the car alone for at least thirty min.before doing any work.  I also prefer to work with a static discharge wrist strap on one arm any time I am working near or on the air bags.

Ok thanks, definitely beyond me then...it must be coincidental that the dealership adjusted the battery terminals and the air bag light came on...just timing I guess...thanks again...

[asharma]

On 5/23/2020 at 3:22 PM, JFP in PA said:

 

I have very rarely seen side air bag wires chafe inside the door unless the window mechanism caught them and tore them up.  Usually, the problem is where the wire harness exits the door and enters the main body.  In any case, you need to be electrically testing the entire harness, not just looking for obvious damage.

 

You need to disconnect the battery and leave the car alone for at least thirty min.before doing any work.  I also prefer to work with a static discharge wrist strap on one arm any time I am working near or on the air bags.

Just wanted to double check...is there a snowballs chance in hell that a bad battery could throw such a specific code (801b)...I’ve been reading the forums this weekend and noticed a couple cases where a low battery caused an airbag code...
 

if you think there is a chance, I could start with a battery load test...the battery is 8 years old...thanks 

 

edit: the battery is currently not holding a charge as I gassed up today and the battery was dead, just barely managed to get it started...it’s currently on a trickle charger and shows charged but when I drive, it quickly drains...

Edited May 24, 2020 by asharma

[Loren]

1 hour ago, asharma said:

Just wanted to double check...is there a snowballs chance in hell that a bad battery could throw such a specific code (801b)

 

Yes, we have seen a weak battery cause all sorts strange electrical issues.

If the battery is weak or over 4 years old it should likely be replaced.

[asharma]

12 minutes ago, Loren said:

 

Yes, we have seen a weak battery cause all sorts strange electrical issues.

If the battery is weak or over 4 years old it should likely be replaced.

Thanks Loren...ok, will do...sounds like it’s time any way, regardless of whether it fixes the issue or not...

[asharma]

On 5/24/2020 at 7:48 PM, Loren said:

 

Yes, we have seen a weak battery cause all sorts strange electrical issues.

If the battery is weak or over 4 years old it should likely be replaced.

Just a follow up...I did stick a new battery in today, no dice...code 801b keeps coming back after clearing...definitely behaving like a short as something seems to be drawing power from the battery, according to my battery charger...

[Loren]

Then its time to monitor the battery current draw (amp meter) -- then remove one fuse (at a time) looking for the large current draw going away. That will be the circut with your draw or short.

[asharma]

6 minutes ago, Loren said:

Then its time to monitor the battery current draw (amp meter) -- then remove one fuse (at a time) looking for the large current draw going away. That will be the circut with your draw or short.

Thanks Loren, given its code 801b, doesn’t that code already indicate its in the passenger side airbag harness?

[Loren]

Not necessarily. Airbags don't take much power at all.

Best to double check where your draw is.

 

[asharma]

8 hours ago, Loren said:

Not necessarily. Airbags don't take much power at all.

Best to double check where your draw is.

 

Makes sense...appreciate the guidance... 🙂

[asharma]

21 hours ago, Loren said:

Not necessarily. Airbags don't take much power at all.

Best to double check where your draw is.

 

I have an amp meter on my battery charger...it seems to me the second I stick the key in, the meter goes from charged at 2 amps to like 8 amps, a 6 amp drop...I removed both driver and passenger seat 30amp fuses, no change...are there certain fuses you would start with? BTW, this is a 2008 RS60 Spyder (BoxsterS) with 8500 original miles...thanks

 

edit...please ignore this post...my amp meter was simply showing me that when the key was inserted, it went back to 10 amps of charging instead of a 2 amp trickle charge when charged...I still don’t know where the Short is however but trying to get it into a shop this week...

Edited May 26, 2020 by asharma

[asharma]

On 5/25/2020 at 10:05 PM, Loren said:

Not necessarily. Airbags don't take much power at all.

Best to double check where your draw is.

 

Hi, I went to the dealer today...they were finally able to clear the airbag code which they attributed to a voltage glitch, perhaps when a battery gets low etc previously they were unable to clear it but today they said it went from active to passive...

 

i did install a new battery the other day (After the car threw the airbag code) and trying to determine if there is actually a draw on it...when I came home today, I hooked my trickle charger up (1.1A) and it took 7 hours to fully charge...the other day I hooked my 10A charger up after a 30 minute drive and it took 30 min to fully charge...Does that sound like there is a draw on it from somewhere? Thanks

Edited June 4, 2020 by asharma

[asharma]

21 hours ago, asharma said:

Hi, I went to the dealer today...they were finally able to clear the airbag code which they attributed to a voltage glitch, perhaps when a battery gets low etc previously they were unable to clear it but today they said it went from active to passive...

 

i did install a new battery the other day (After the car threw the airbag code) and trying to determine if there is actually a draw on it...when I came home today, I hooked my trickle charger up (1.1A) and it took 7 hours to fully charge...the other day I hooked my 10A charger up after a 30 minute drive and it took 30 min to fully charge...Does that sound like there is a draw on it from somewhere? Thanks

Any feedback would be appreciated folks...Today, full charge (showing on my trickle charger) , backed out, washed it, had doors open etc, drove back in, 20 min to fully recharge on 10 amp charger...Does that sound right or could there be an unwanted draw causing this?

[RFM]

Do you lock the car with the remote ? This is necessary to get the systems into sleep mode after some time, for minimum power consumption.