I recently replaced my battery in my 2004 Infiniti G35 6MT and found the lack of instructions annoying so I am posting the steps I took to replace the battery. I hope this helps others that either don’t live next to an Infiniti dealer or just want to do it themselves (I fall into both categories). Any image can be clicked on the get a larger version.
Step 1
Remove the rubber lining around the battery cover that is closest to the windshield
Step 2
Remove the pins from the battery cover using a flathead screw driver. These should pop out rather easily. There should be 5 that you have to remove.
Step 3
Remove the battery terminals from the battery using either a wrench or a socket. The negative cord should be easy to move out of the way, but the positive cord was a little tougher since it had some extra hardware on it.
Step 4
Unplug the two plugs from the bottom of the positive cord in order to maneuver it out of the way a little better. Using a flatehead screwdriver push in on the little bracket that is holding each plug in place.
Step 5
Unbolt the crossbar holding the battery in place. I only unbolted the end that is clearly visible and then unhooked the other end by twisting it around until it came unhooked.
Step 6
Remove the battery. This can be tricky since there is very little clearance. You may need to bend the plastic covering a little in order to have enough room to get it out.
Now that you have the battery out, you should be able to reverse the steps to put everything back together. Back in step 1 when you are replacing the pins, make sure to slide the pin up a little before pressing it into the hole. The image below should help out.
After I got everything hooked back up I fired up the car and I was back on the road.
Tim Banks 
You can take off the plastic trim under the windshield wipers easily, too, to avoid having to navigate around it. Take off weatherstripping, then remove two more of those plastic pins, and the left half of the plastic trim under the windshield pulls out, too. It has three tabs on the backside that grip the windshield glass, so after freeing pin on right side, pull down and in to release.
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Followed the instruction and I am back in business. I found that if I remove the plastic trim under the windshield wipers as suggested by VanceWade, I did not need to do step 4 Unplug the two plugs from the bottom of the positive cord. Hope this simplifies thing a bit for others.
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Excellent. Used the instructions above, thanks for taking the time to take pics and give detailed instructions. It went very smooth. Thanks also to VanceWade’s additional suggestion which did allow it to go smoothly.
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Very helpful, Tim. Replaced my battery today without any issues. The pictures and the notes were extremely useful! I wish it was easier to get these details in the Infiniti Owner’s Manual. Thanks again…
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+1 to thank you for taking time to take photos and publish this guide!
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very helpful – thanks for your great pics!
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This guide with pictures was very helpful. It took me 20 minutes to swap out the battery. I saved almost $100 by doing this myself rather than going to the dealer. Thanks!
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Fantastic! I had never replaced a battery myself but had no problems and even skipped step 4. Thanks so much!
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First hit in my Google results, only link I needed. Perfect walk-thru! Sometimes it just helps to see an example first. On the road in 15 minutes…
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Excellent instructions. I am not replacing the battery, but am checking my fuse box for the A/C does not work, hoping it is a relay. Thank you.
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Thank you so much for this tutorial with pictures! As other commentors mentioned, using VanceWade’s advice made it easier to remove the battery. Looks like the stock batteries in these cars lasted quite a while. 🙂
10mm – the spanner and/or socket size needed to loosen all bolts/nuts in this process.
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Thanks for the instructions!
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Thank you so much! This was a life saver. Was standing outside autozone trying to get it done. I couldn’t have without this walk through. Awesome!
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Can’t thank you enough. Was trying to do this after a very long day and you cut my frustration and time in half. Tim, thanks for taking the time to help others!
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Thank you so much!!! Incredibly easy and I am not too handy! Saved me a bundle! Can’t thank you enough!!!!
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Thanks so much Tim for posting! I used Vance’s tip on removing the moulding and was able to complete it. The hardest part was getting the pins back in, and now I see that I should have pulled that tab down to the middle first. Oh well, got most of them back in, dropped a couple when trying to replace them though. All in all I’m very happy with my work 🙂
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This was extremely helpful and I was able to get the battery replaced in 20 mins. Thanks Tim for the post and Wade for the additional info.
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EXCELLENT INSTRUCTIONS and PICTURES
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Thanks for taking the time to do this Tim! Very helpful for a novice like me!
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Thx from your old isc collegie
It’s a bitch getting it out
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You would never make it as a technician. Number 1 rule with batteries…. Positive comes off first and Negative goes on first. All credibility is ruined just from that.
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Gents,
Many thanks. I took the initial shroud off, saw the additional hardware on the +ve post and came close to quitting in favour of a jump start and drop off at the dealership. A quick google, however took me to this site, saw photos and Vance Wade’s additional comments and “Bob’s your uncle.” My wife thinks I’m a genius and I reckon I saved some serious cash.
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Wow!!!!……I was sooooo not looking forward to pulling my battery once I saw what I was dealing with. Then I ran across your very detailed site. Yes I skipped step #4 but none the less this was so valuable. Thanks for taking the time to put this together. The operation took me 15 minutes. I timed it.
Tools:
Flathead screwdriver…(for battery cover)
10mm socket…..(for battery terminals)
mini adjustable wrench…..(for crossbar over battery)
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Tim – just purchased my 2004 G35 – only 30k miles (verified thru carfax and vin check). Although I’ve changed batteries in numerous cars, over 30 years – your ‘tutorial’ was excellent. 18 minutes, 26 seconds, had my wife ‘time’ me. thanks again
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Hey John. I’m happy the article helped you out! I’m super jealous of your purchase. I ended up wrecking my Infiniti a few years ago and have missed it a lot. One of these days I’ll have to get another one. Have fun and thanks again.
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Thanks, but he pictures aren’t working anymore.
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