Battery and Alternator Question
 

I've been having a situation with my battery dying and after some investigating I have a question. First off here's the situation. My 99 D2 is a couple months new to me from original owner. It has an Odyssey PC 1500 with a date code of 04/07 on it. 825CCA. The original owner did not use this vehicle much and it sat a lot in the last 7 years. I spoke with tech at Odyssey and this batteries can sit on the shelf for 2 years, but if sitting connected it can damage the battery. They said it could possibly be brought back to life by completely discharging and recharging with a high amperage battery charger. Note that Sears and Auto Parts stores do not know how to charge these batteries. Neither did I. But these batteries require a high amperage charge. This battery also requires 14.4v to 14.8v to charge. The voltage at my battery terminals at idle is 13.6. The auto parts store tested the alternator and it came out at 13.7 to 13.9 when revving with loads and without loads. The tech at Odyssey said that voltage is not sufficient and will not charge the battery. I'm pretty sure Ii'm going to get a new battery and have read threads and see people are happy with the Diehard Platinum which is the same as the Odyssey. The tech rep at Enrsys said these two batteries come of the same line with pretty much the same parts.

On to my questions ... Is 13.7 acceptable output for an alternator or do I need a new one? There is a Bosch from Land Rover in there now. if i get a new Sears Diehard Platinum battery (from Enersys) and it takes 14.4 v to charge, am I also in need of a new hight output alternator? Or is the voltage requirements of that battery beyond the spec of the Bosch alternator? Just trying to figure out my next move. Thanks for advice and input.

And for those that are curious or searching on similar issues here's some history that lead up to the battery problem which made it confusing to diagnose. This is not my primary vehicle and not driven daily. It all started after I moved the front bumper a tad to fit my larger tires and then after that the SRS light came on. And then the next day it didn't start and just had a rapid clicking noise with the SRS light flickering. After reading a few threads I found that the SRS light could be related to low voltage. After having my battery charged it was down again after 2 days. So I thought I had a drain. Bought a multimeter and only found .02 mA when vehicle is sitting. Called Odyssey and they explained my battery and that it hasn't been fully charged and that my alternator is not putting out voltage in spec with the battery's requirements and that it will not charge fully.

1. If you moved bumper you may have disturbed the main ground bond from (-) negative battery terminal to frame. Would be a good idea to remove and clean, re-install. You can also clean up large wire connections in front of underhood fuse box. Every little voltage drop adds up.

2. Expected output from Rover is on the order of 13.8 - 14.4 volts. New battery should be fine.

3. A "new" battery will still need to be charged, just driving around for 30 minutes at a time won't do it.

Checked a little more, the Odessey web site does not download very fast today. The battery you have is most likely an AGM (absorbed glass mat) which makes it spill proof, no top to open, etc. AGM batteries can accept various charge voltages, based on temperature. I would point out that underhood temp is far different from outside temp. I checked another big AGM producer, they list 13.8 volts as optimum charge voltage for temp range of 110 F, and 14.4 volts for 75 F, and higher when colder.

So use of an AGM style battery might not always be the best option with a Rover, Bosch alternator or not. However, if charged to 90% capacity, would it still work? Most likely. Would it give customer-no-service a reason to complain? Yes.

By cleaning up all your terminal connections, both positive and negative, you may be ablle to get your voltage up to 14.2, perhaps 14.4. At some point it becomes a function of the diodes (are they all working) and the regulator (what voltage is it designed to put out?).

Thanks for the info. Yes the Odyssey is an AGM; info here ODYSSEY Batteries mine is rated at 825 CCA. So it seems my alternator is okay and at the low end of spec. I will clean all connections, although they look super clean. I didn't understand how the ground had anything to do with the bumper as there were just a few bolts and the fog light electrical connectors to undo. Based on the Odssey great service tech rep; it's most likely that my battery has some damage because of it's idle sitting from it's previous owner. It could be possible to bring it to life again, but I'd like to just get a new battery. I was going to get the same (Sears Diehard Platinum), but now I'm not sure. I'll report back on the voltage after I clean it up.

You may not have touched the frame ground, but it might have shifted. Just follow negative wire from battery to the spot where it bolts on, remove and scrub, etc.

Jay,
If you still have issues, send me your number and I'll be glad to walk you thru your questions.
Yes, 13.7 is just about to low, should be in the 13.6 to 14.4 range. Why do you feel you need a heavier alternator?

Well I don't think I need a heavier alternator. Was more just wondering if mine was in spec and a good match for the Odyssey AGM battery. Today I went ahead and got an Interstate battery with 800 CCA. Cleaned the terminals and ground and installed the new battery. On start I now had the SRS, ABS, TC, and Hill Descent lights all lit up. SRS has been on since I fiddled with the bumper and right before my dead battery problems. I turned the engine off and restarted and the 3 lights went out but SRS stayed on. I drove around and the ABS, TC, & Hill Descent lights all came on again. I turned the engine off at the next red light and restarted and the lights were off again, SRS still on. I don't understand why putting in a new battery would cause this problem? I will check the belt pretensioner connections next to see if this is the SRS light cause.

SRS is air bag system. The impact sensor on a D2 is inside the air bag computer, under console. Some older systems had things near bumpers, etc. From the RAVE:



be serviced. It must be replaced if it is faulty.

and

SRS warning lamp

The SRS warning lamp illuminates for 5 seconds during system readiness check on starting the engine. The SRS

warning lamp extinguishes for one second after the system readiness check is performed. If a fault is present the

warning lamp then illuminates continuously. If no fault is present, the SRS warning lamp remains extinguished. If a

system fault occurs in excess of two seconds after the readiness check has been completed, the SRS warning lamp

illuminates for that ignition cycle. It remains illuminated for a minimum of 12 seconds -

4 seconds for all fault

conditions.

The SRS warning lamp will only illuminate for low voltage concerns while the low voltage condition is present. If the

low voltage condition is corrected, the SRS warning lamp extinguishes and the fault is recorded in the DCU's memory.

So it would appear low battery volts can make SRS light come on, but it should clear after a few drive cycles. Could also be one of the components unplugged. See RAVE for layout under restraint systems, AND only work on it with battery disconnected. Lots of tiny explosive charges to tighten seat belts, deploy air bags, etc. They are called squibs. If not cleared up, it's dealer time.

Wiring diagram attached, nothing under hood except fuse, might check those to see if cables have been wiggled too far, etc., wire or bolt loose.

You may want to send me your number so I can walk you thru the 3 amigos, which you want to fix before they set a hard fault and stay on.