B5 TDI battery upgrade

The North American B5 Passat TDI came with a 72Ah battery, while the Golf and Jetta TDIs of the same vintage came with the larger 80Ah. The New Beetle had to make do with the 72Ah unit for space limits, however the Passat has no such limits. In fact, most Audi A4s, which ride on the same platform, came from the factory with the larger battery.

Old battery installed:



Old and new batteries:



So here is how you upgrade your Passat's battery when the time comes

The battery I am using is an Entertec model, from Volkswagen. I have found these are not only an excellent battery, but a pretty good value. You can also use an Interstate MTP-H7, which is also an 80Ah battery. Although most Interstate retailers will not stock one, they can all get one. The VW part number for the 80Ah battery is 000-915-105-AG (the standard 72Ah is the AF suffix). You will also need to order the different battery hold down (they call it a clamping strip) 8D1-803-123-D. Any Volkswagen or Audi dealer can order you one of these.

Here is the old battery hold down and the new one:



First, remove the cowl cover, and if you have a memory saver you can plug that into the cigarette lighter now (if you do not, you will lose the memory on your MFA, clock, and your ECU will lose its readiness monitors).

Remove the negative battery cable completely which requires a 10mm on the battery clamp and a 13mm on the body grounding point capnut.

Remove the 10mm nut holding the positive lead from the battery clamp going off to the car's electrical system (heading towards the brake master cylinder area). Caution: this leg will STILL HAVE LIVE POWER if you are using a memory saver, so cover it and do not let it touch anything metal!!!

Next remove the positive battery clamp 10mm holder, and pop the positive cable holder out of the body at the firewall, and swing it around and out of the way, over near the A/C pipes and pollen filter. This should not have any power on it now, as this is the main leg to the starter and alternator.

Then pop both ends of the vacuum tube running from the firewall pass-through grommet to the brake booster. There will be a hiss when you remove it from the booster, that is normal. Take care not to kink this tube.

Remove the battery vent tube from the side of the battery (positive cable side) and position aside.

Remove the bolt from the battery hold-down clamp, this is a 13mm, then lift the clamp away.

Now the battery is ready to come out. You will need to slide and tilt it towards the pollen filter side of the car a bit to get it to come out. Be careful not to lose grip of it and drop it on anything!

Now is the perfect time to clean UNDER the battery. I prefer to wipe the battery tray down and use some spray wax under that area, and make sure your grounding stud is clean and free of any rust or corrosion.

Locate the threaded hole in the body near the grounding stud. Depending on how much rust proofing your car recieved, it may be partially covered with goo. Clean that up, and make sure the threads easily take the hold down bolt. The thread is 8 x 1.25 if you need to use a thread chaser to clean it up, but generally some solvent or brake cleaner will remove any rustproofing and reveal a squeaky-clean virgin threaded hole.

Next, slide your new battery in.... take care is it is a little longer so it will be an even tighter fit. Make certain you have it oriented correcty, and make sure the vent plug is in the correct side of the battery, so you can reattach the vent tube on the opposite side.

Install the new clamp like this:



It is right next to the grounding lug, and then snug the bolt (it need not be very tight). Make sure it is at a right angle to the battery. Make sure the battery vent tube is put in.

Then reinstall the vacuum tube, popping it securely into the pass-through grommet and booster. Then lay the positive cable back over, attach it, attach the smaller lead from the car to the stud on the cable end, and pop the cable stay back into the firewall.

Put your ground cable back on, and snug the fasteners. Make sure the ground cable tang is at right angles to the battery. Once both cables are attached, you can remove your memory saver.

Reinstall the cowl cover, start the engine and let it idle for about 15 seconds BEFORE moving the car, so that the brake booster has adequate time to build boost for the brakes.

If you did not use a memory saver, you will need to reset your clock, and drive the car for all the readiness monitors to run (these will do so anyways, so you do not have to drive the car right away).

Dispose of your old battery in the proper manner.

Excellent write up! Can we make this a sticky please?

Nice Christmas present OH! I think I'm going with this install when my battery kicks it. The new battery looks like it has the removable screw caps under the sticker like the Varta. Is that correct?

Merry Christmas and a Happy New Year!
Thanks for all your great work on the forum. It is much appricated.

Thanks, although you could have been a bit more timely and put this out yesterday when I was changing my battery

This is def something to consider

Excellent thread. Thanks OH.

Quick Q: if going with the Interstate MTP H-7, do we still need to get the new battery clamping strip? Reason I ask is Interstate has a distribution center in my city, so thought I'd try to get one of the blemished ones for $30-ish.

Thanks again, OH. Very helpful.

Yes, the H7 will require the new clamp, as it is dimensionally identical to the AG suffix 80Ah Enertec.

Brian: thanks for the effort and the part numbers. My OEM battery is *still* going strong, but after 5 years and going on 80K miles, I have added it's replacement to my list of Preventive Maintenace items to complete this Spring or sooner (depending on my new hip rehabilitation progress).

I have a new relay 219 on the list along with a complete underside inspection of axles, boots, motor mounts, and the like.

I also have OEM mud flaps and a rear deck lid spoiler to install. Maybe new brakes and a brake fluid flush too!

Tony

A nice XMAS present to the group! Procedure and alternative battery (I have had excellent resutls with Interstate Batteries), cool. Thank you.

What are Rediness Monitors and how does that affect operations when you get going again?

Thank you Oilhammer. I am in need of a battery, and glad to add a boost in battery capacity. Excellent writeup with great photos

FYI for others, My local VW dealer quoted $19.80 for the hold down, and $110 for the battery (000-915-105-DH).

They said the -DH- was a replacement for the -AG-.

How handy! I am planning on putting a new battery in my passat probably this summer. Thanks OH!

Readiness monitors are the checks that your engine ECU does periodically to make sure everything is working normally. If one fails, it will set a DTC in the ECU's memory, and if it fails enough, it will illuminate the MIL.

Any time the ECU loses its KAM (keep alive memory) all these monitors can be wiped clean, and will need to be reset by driving the car. This is not anything to worry about, except that if you are like us here in STL and your car requires an OBD check for inspections, you won't want to disconnect your battery then bring the car in for the OBD check, because it will fail due to unset readiness.

Neat post, many thanks once again!

Hey 'Hammer....Merry Chrsitmas!

Which battery did you put in my BHW? (apparently I'm too lazy to look...LOL!).

There's a long thread over in the Ontario Forum about batteries.
http://forums.tdiclub.com/showthread.php?t=267031&page=2

If you go to post #25 by TDI Power, and his subsequent posts, you'll see that for cold cranking (like up here in Canada), the SAE spec CCA is what is more important as it's measured at low temps, whereas the European DIN spec AH is measured at balmy temps. Oddly, TDI Power comes from Savannah, GA, but his arguments seem reasonable to me.

Here's a quote he posted in post #56:

Do not get hung up on Ah capacity of batteries . It has very little to do with the number one job of the battery which is to start your car. The 20 hour rate {ampere hours} is the ability of the battery to carry a low rate of discharge . For Example: A 100Ah Battery will carry a 5 amp load for 20 hrs before dropping to voltage of 1.75 volts per cell, or 10.5 volts on a 12 volt battery.5x20 = 100ah.This rate is measured at 80deg F when the battery is 100% efficient.Cold Cranking {CCA} is a rating taken at 40 deg F when the battery is only 40% efficient. The alternator carries the basic electrical load after the car starts.

Click to expand...

Anyway, he is recommending a couple of Energizer batteries with high SAE CCA, rather than the VW battery with the high DIN AH.

You guys should check the Walmart for Energizer 94R

OEM battery
Make:Energizer
Model:108-94R
CA: 965 A
CCA: 765 A
Warranty: 3-Year free replacement 9-Year prorated A

Click to expand...

Anybody have any experience mounting one of these or other Energizer batteries in a Passat?
EDIT: or rather than hijack this thread, the moderator should move it to a new one?

A 94R battery is physically the same size as the 80Ah battery oilhammer installed.

Thanks for the info oilhammer. I am changing out my battery since the original is starting to "sound" weak - especially on the colder mornings. My local dealer quoted me $99 for the 80Ah "AG" battery. Found the Energizer 94R at Sam's Club for $84.66 so I am going with that one. I noticed that the Energizers are manufactured by Johnson Controls who are the same folks that make the Interstate batteries - so that inspires some confidence. Thanks again for the excellent write up.

MOGolf said:

A 94R battery is physically the same size as the 80Ah battery oilhammer installed.

Click to expand...

But with 125 Amps more cranking juice, and it only costs $0.11/A, 3-Years free replacement & 8-Years prorated warranty.

blaz said:

...Oddly, TDI Power comes from Savannah, GA, but his arguments seem reasonable to me.

Click to expand...

I have to give credit where credit is due to my EE collegue, when I worked @ Bombardier Aerospace in Montreal, Quebec, Canada few years ago. He said, never mind about the Ah, Ah is useless in cold temp. Buy a battery with the largest CCA that fits w/in the battery tray/compartment and you won't be sorry. My father who is an EE, said the same thing too. The person whom you quoted, who is a TDIer EE, more or less said the same thing too. So, I have three EEs who give their highly no BS recommendations plus the SAE study-can't go wrong, and has always worked. So, that's the bonus experience I got from working in Montreal.

passatpete said:

I noticed that the Energizers are manufactured by Johnson Controls who are the same folks that make the Interstate batteries

Click to expand...

Johnson Controls Power Solutions AG is also the parent company of Varta. The info below was found on the Johnson website:

- Lead acid batteries sold under private label brands as well as our own VARTA, Heliar, LTH and OPTIMA® brand names.

- Major customers include Walmart, Sam’s Club, Advance Auto Parts, AutoZone, Costco, Sears, Interstate Battery System of America, Daimler, BMW, Ford, General Motors, Toyota, Volkswagen, Chery, SAIC

Yes, JCI makes a wide variety of both original equipment, OE-branded dealer install, and aftermarket jobber batteries.

I think there are only a handful of batteries available in this continent, made by just a few manufacturers. JCI, Exide, Deka, and a couple others.

Now you tell me! LOL... I installed a Dekka 80 amp battery by removing the mounting shelf, drilling a new mounting hole and installing a Heli-Coil in the tapped hole. There are probably 3 threads in the shelf (it's fairly thick) as well as the rest of the length of the insert below. I trimmed the original mounting clamp bracket to account for the reduced clearance on the end of the tray and tightened it down. Works like a charm. Had no idea there was a 'big battery' clamp available.

Take Care

Killed it this morning

About 5F this morning and the car almost started a few times before the battery gave up the ghost. Luckily I live very close to work and a coworker stopped by on his way home to jump start it. I can't plug in at home because home is an apartment complex.

Lost all the Kam memory, clock, Mfa etc. Car idled like crap. I have the bracket on order and it won't be here till late in the week. I am going to Wally world and get the energizer today and try not to toss the car around too much .

9F on the display this morning. 72Ah battery installed in Oct. I ignored the GP light (like I've posted), and it starts up like a summer day. Just the usual roughness of a diesel engine for a few seconds before the cylinders get some warmth to them and it idled normally.

glenn- can you elaborate on how you ignore the GP light? (i didn't see that post )
thanks

tditom said:

glenn- can you elaborate on how you ignore the GP light? (i didn't see that post )
thanks

Click to expand...

My apologies for off topic. http://forums.tdiclub.com/showpost.php?p=2798065&postcount=28

If you must cycle the plugs again, wait at least 30 seconds in the OFF position.

I am using the 11v plugs due to emissions testing and not getting the recall reflash. I am about to wire up a manual 12v relay for the plugs. I am sure this car would have started faster with proper voltage.

thanks. my technique is to wait for the audible relay click (as you can see from my sig i have the older models that use the mechanical relay)

I will second the comments about battery Cold Cranking Amps being the most important parameter. In cars, the battery has just a couple of important functions. Most noticeable, it has to crank the engine well enough to start it, even in the coldest temperature wherever you live. Also important in modern cars with a microprocessor for most everything, it must keep those computers & their memories alive at all times. If your battery has sufficient CCA, the rest is taken care of. The only added comment is that it is worthwhile to buy a battery that is well-enough made that it will keep on delivering those needed CCA over time.

Ampere Hours capacity is only a big deal if you plan to run something like the headlights for long periods without the engine running. Not a common need for the average motorist.

My new battery from wally world is a type 49n (made by Exide) which is the same size as the 94r. Oddly enough it is the replacement specified by the battery picker book. The 94r had 730cca and the 49n has 850cca with 1000ca warm. I will post a photo if anyone wants to see the battery label.

The big test will be in the morning. There is supposed to be single digit morning temps most of the week.