DaveK

My turbo has just thrown an offside front wheel speed sensor fault for the second time in a month or so (ABS and PSM lights came on).

While I was reading the code with Durametric, I checked for other fault codes and found the instrument cluster had logged 9130. I know I've seen that when I checked the codes one time before (and cleared them).

I've done a search and it suggests that it might be a battery / alternator issue. Is that correct?

I don't know how old the battery is - it appears to be Lucas (which I assume is not OEM) and only seems to take up about 2/3rs of the battery tray. Can't see what rating it is without taking it out.

Battery voltage looks good when the car is running (from the gauge) so I think the alternator is probably OK. If this fault code definitely is battery / alternator will a new battery solve it?

wross996tt

uh...there is no 9130...could you post the correct code #.

DaveK

Durametric thinks there is.

It's also mentioned in these two threads :

https://rennlist.com/forums/996-turb...r-warning.html

https://rennlist.com/forums/996-turb...r-failure.html

wross996tt

Yes, I understand that durametric is reporting this code #, but it is difficult to translate to a Porsche code (e.g., P0563). here is an explanation of DME 7.8 code text. Perhaps contact durametric for an explanation of the code. I would just clear the code and see if it comes back.

DaveK

OK - thanks.

I have previously cleared it - I can't remember when it was, but I do know I made sure there were no codes when I got it back from the dealer just over a week ago (and I suspect the code was logged then).

I'll mail Durametric and see if they can add anything. The car will probably need to go back to the dealer (yet again) for them to look into the wheel speed sensor fault anyway so they should be able to read it with the proper Porsche kit.

wross996tt

Yes those sensors can be a PIA...make sure all the connections are good.

DaveK

I checked the connections on the wheel speed sensor today. Looked fine, and seemed water tight - I sprayed some contact cleaner on them and reconnected them anyway. Dealer has ordered a replacement sensor and will check / replace next week.

I think I understand the cause of the instrument cluster power supply code now (no answer from Durametric yet). When I started the car today (from fully cold) the battery voltage gauge sat at about 11v. It stayed there for a good 10s - I did try revving the car slightly but I'm not convinced that was what brought it back to normal.

I've started the car a couple of times since - once when warm and once when it had cooled down (but not fully cold) and the gauge went straight to around 13v. I watched it a couple of times at idle, and it looks like it's sometimes around 12.5v.

So, I suspect I might have some issue with the alternator - does it have a belt, and could it be slipping when cold? It's a bit hard to see much with the airbox in the way. I am still suspicious of the battery but not sure that would cause the low reading I saw from cold, since the engine was running.

Loren

Fault Code 9130 Supply Voltage
Possible cause of fault:
- Battery voltage is low

If the battery has been changed or disconnected - then this is a common fault.
I would erase the fault and if it comes back then investigate the battery and charging circuit.

DaveK

Thanks. I think your post crossed with mine. I assume the voltage I saw when I started the car from cold is not normal. And I suspect that points to charging system rather than battery?

I'm fairly sure the car was clear of codes since the last time the battery was disconnected - but I'll clear it to be sure, and check it over the next few days.

Macster

With the benefit of reading the entire thread I'm going to offer WAG that the battery is suspect. Lucas? Physically small. Unknown date of manufacturer? Unknown capacity? Car probably sees limited/sporadic use?

Check with Porsche dealer parts department but Porsche might have issued a TSB or something similar upgrading the size/capacity of the battery used in the car. When I went to replace the OEM battery in my 02 Boxster parts department manager looked up battery based on car's VIN and found Porsche had issued a new part number which mapped to a larger capacity (and size) battery. More AH, more CCA and physically larger. Same height, width, but length increased by some so the next hold down hole in the bottom of the battery box needed to be used. It had a threaded insert underneath so dropping in the new/larger battery a piece of cake (though a real heavy piece of cake...).

If you want to buy a non-OEM/Porsche battery that's up to you, but be sure you buy the correct size/capacity battery and this purchase is based on the current battery specified for the car. Before you buy measure battery size and be sure it will fit and be sure that if longer it has a length that matches the holddown hole in the bottom of the battery tray. (I assume the Turbo's tray similar to my Boxster's though I've never had a close look at the Turbo's tray since I've owned the car.

Up to you if you want to replace the battery but far more batteries fail than alternators. If you can find a known good battery that will fit in the car's tray and see if the voltage across the battery terminals at 13.8v or a bit higher with engine idling which suggests a good charging system that's up to you.

I do not know if I would put much trust in the in-dash voltmeter, although the one in my car's dash appears to display what I believe the actual voltage would be were I to bother measuring it using a volt/ohm meter at the battery terminals.

Sincerely,

Macster.

DaveK

Car sees daily use (although perhaps not every day over the Christmas period). But you're right about the other points, so I tend to agree that replacing the battery is probably a sensible first step.

On my 964, I've always used Bosch and been happy with them. Don't know what OEM is on the turbo - but I'd fully expect OPC prices for a battery to be entirely comical. Halfords (the main car parts store here) usually lists the recommended Bosch battery, so I might pay them a visit in the next few days.

Macster

I'm sure the OPC price for a battery beyond comical, but my 02 Boxster's OEM battery lasted nearly 7 years and I have read too many horror stories of someone buying a discount battery and suffering from this. Not everone, sure.

As an aside: I was a bit dismayed to see my 03 Turbo came with an Interstate battery, obviously having been replaced cause the car driven so few miles by the 1st owner. I will leave the battery alone for now but at the first sign of battery troubles out it comes and in goes a Porsche battery.

Anyhow, back to the Boxster: Replacing the battery with another just like it and hopefully receiving the same trouble free service from this new battery the original gave me was worth the extra cost.

Given the running costs from driving my Boxster 220K miles (at battery replacement time though mileage is nearly 227K miles now) the difference in the cost between a Porsche battery and another lower cost battery with possibly questionable performance and longevity amounts to just a tiny fraction of what I've spent on oil/filter services, filters, tires, alignment, brakes, etc.

Now if a new battery was required more often if it was their nature to be replaced more often, then I might be tempted to seek out a lower cost but still suitable alternate battery.

Sincerely,

Macster.