Perry where are you taking the readings from?

 

Just the gauge in the dash. I realize it can vary but it has always been rock steady and only recently have I noticed it moving around. I am not techy so readings from elsewhere aren't gonna happen.

 

I will just say that my gage is total crap. Read the jump post and compare it to your readings in the dash. That way you know if your gage is accurate or not.

 

I was going to say that the voltage should not drop much at all with a good battery. Steady decline while you are watching it would indicate to me that you don't have all your cold cranking amps there.

last year when I went to green bay we went to the dyno. Lots of cars need jumps to start. I laughed at them but after three or four starts suddenly mine wouldn't start either

New battery and have no problems since (sears battery)

 

Ok charged the battery fully today. Put the load on it twice and it held good. Kept the charger on it till it was maxed out. Started the car and volt Gage was correct with the battery voltage. The radar detector also is not reseting. Maybe this is a weak battery problem. I'm going to do readings again when the radar detector starts resetting again. More to come later.

 

Test the fluid in the battery with one of those little floating-ball testers they sell at parts places. <$2 at WalMart on the car battery rack. The test is for specific gravity of the electrolyte. As the battery loses capacity the acid gets weaker and the specific gravity drops. Too low indicates a weak battery, time for a new one. A weak battery will take its toll on the alternator and the rest of the electrical system in the car, since it takes a lot of current to get it back to nominal terminal voltage. Lots of alternator and other electrical problems can be correctly blamed on old/worn/weak batteries.

 

Thanks Bob. I'll definitely be keeping a keen eye on the battery from here on out. I still may change it anyways since I don't know how old it is.

 

Ok here's a update. After putting the correct wire on the cigarette lighter jack and load testing the battery and heavy recharging the battery I have had no low voltage warnings on my radar detector even with evrything running. One of the other things I did find while troubleshooting this problem was both bolts for the CE panel were backed way off. Not sure if that would do anything or not. The one bad thing is now my A/C fan isn't running I probably just knocked a fuse loose while I was messing down there.(Fingers crossed) Sure beats listening to a radar detector reseting every time I hit my breaks. Thanks for the help everyone it is much appreciated.

 

Ok, I guess I may have a gauge issue as well. I became very concerned in the last week as under load a/c on high the guage was reading 10-11. I got a new DMM and check out all I could. Here are the readings -

AT IDLE:

Battery Jump Post Guage
All OFF 12.03 12.02
IDLE 14.07 14.18 12-12.5
LIGHTS ON w/ A/C on HIGH 12.60 12.35 10.5 - 11

I guess that tells me my guage is wrong? I have had no starting issues. But, I have had some concerns when on the road in 100 degree temps with a/c on high and in stop and go traffic and the guage reading 10.5 that any minute I was going to go dead.

Are my assumptions correct? Or are there other checks I should make?

 

Parker check your battery 1st thing. After all the work I did my battery was weak. I had no start issues either. The A/C is a huge drain on my car. I would bet even too much of a drain. Run the A/C in town with a bunch of stop and go driving and my battery was noticeably down. My advice is look hard at the battery before you go through what I just did. Make sure to load test it. Jason

 

It is very probable that the gauge, alternator and battery are good. I would suspect the wiring to the gauge. Porsche chose to power the gauge off of a multi-use circuit rather than direct from a primary source. As a result there are at least 7 connections between the battery and the gauge which can build up resistance and affect the reading. Cleaning all of the contacts on the fuse/relay panel would be a good start and possibly give you a more correct reading.

Dennis

 

Thanks for the input. I am in the process of some late spring cleaning of grounds and the CE panel. Haven't finished yet.

Jason, I will do a hard drive today and retest. I have a new (11/07) battery and have gotten rid of a drain issue after I removed the PO's wierd amp, sub, DVD player confirguration. I leave the car idle for over 2 weeks and it starts right up.

Thanks again for the help guys.

 

Mine was never a start issue. It was an accessory issue. I think these cars start very easy especially with a few miles on them. The advice about cleaning the fuse connections on the CE panel and the grounds is good advice. I'm doing my CE today or tomorrow it's pretty gunked up from age.

 

Got something else to add to this. My gage has been reading crap as of late but I came out today and it was reading perfect all the way to work. The only difference today compaired to others was that it was very cold. Coldest so far. Does this mean anything to anybody out there of where I should look for the problem?

 

Well its almost certainly a connnection issue - pod connectors are most likely because they are low force and susceptible to surface oxidation.

You can also measure the voltage at the top of the CE panel & see if it also fluctuates - if it does - clean these connections & secure tightly & also at the front jump post (you can use more agressive cleaning of both here - but protect after you screw it all back together with a contact protectant).

I'd start with the pod connectors unless you see voltage issues elsewhere - but clean gently - many times people make issues worse by removing too much surface material and thereby further loosening the connections - don't forget to clean (also make sure you clean the connector side as well as the PCB side - e.g. spray it with switch cleaner at least...)


Alan