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Honda Accord Hybrid IMA Batteries



  • Sigh. My 2005 Accord had its IMA batteries replaced under warranty at roughly 60,000 miles. For the past six months, the replacement IMA batteries have been malfunctioning. They updated the software, and the replacement battery continues to drain daily. Soooooooo, today, 2005 Honda Accord Hybrid has 118,000. I "saw" a warranty for 10yr/150,000 battery warranty for the replacements. However, the dealership is certain there is no such warranty. I'm frustrated and disappointed that I've replaced these damned batteries TWICE in eight years. Does anyone have "warranty" intelligence about the replacement batteries?? What would you do if you were me? Mileage is hovering around 24 mpg and batteries are charging themselves from my primary battery. Not impressed, Honda.
  • sclasssclass Posts: 1
    I had the IMA light, software update etc at about 108,000 miles in my 2005 HAH. I began looking for a solution when I found a site that was making grid chargers for Civic Hybrids. This was interesting but I didn't feel it was the correct solution. Next I found a guy buying old Civic battery packs and removing, testing and reconditioning individual battery "sticks". The "sticks" contain individual batteries linked together. I almost ordered the reconditioned "sticks" when I found THE answer--Using a commercially available power source that provides the correct voltage and milliamps to charge/recondition the HAH battery in place.

    Disclaimer: The HAH battery pack contains a high voltage source capable of fatal electrocution. Do not attempt any repairs or contact with the battery without proper training and knowledge of this system. I accept no liability for you working on your HAH battery pack.

    I learned how to completely discharge my battery and did so. I purchased all the necessary equipment and wiring to permit battery charging (reconditioning). Here's what I did:

    Honda Accord Hybrid (HAH) Grid Charger
    1.Purchase BioRad 300 power supply to use as a charger for HAH-eBay
    2. Print BioRad manual for reference--online
    3. Purchase power supply (charge cable) that allow power transfer to HAH
    4. Purchase polarized power socket and plug.
    5. Purchase diodes, fuses and fuse holder.
    6. Purchase power wire and terminals to connect battery and power socket.

    1. Connect the (+) and (-) leads of the power wire to the correct places on the pack. Place a diode as close as possible to the (+) terminal connection. Attach the inline fuse holder and fuse to the socket connection designated (+). The (-) lead only requires a terminal connection, no fuse or diode; attach to the socket connection designated (-). Carefully confirm connections are correct.
    2. Charge cable from power supply requires modification. It is equipped with banana style plugs on both ends. The red lead is (+) and the black lead is (-). Cut off the plugs on one end and attach red lead to the plug terminal that matches the socket connection designated (+). Attach the black lead to the plug terminal that matches the socket connection designated (-). Confirm power output polarity is correct.

    1. Clear any trouble codes if they exist. Remove the key from the ignition.
    2. Plug the charge cable into the BioRad 300 power supply; connect to the polarized socket in the trunk.
    3. Power up the BioRad 300 and set amperage to 400ma. Charge for minimum of 10 hours. Repeat charging on subsequent days for a total of (3) charge sessions.
    4. It’s a good idea to reset the ECM by the fuse removal procedure. This allows system to recalibrate on the new state of hybrid battery.
    5. Note: A single 24-30 hour charge may be required to completely balance all the cells in the pack. If IMA light continues to be set, several or all of the cells may require replacement.
    6. Some owner’s grid charge their cars every night. I’m hopeful I can rebalance my pack and keep in top shape with monthly or weekly charging.
    7. I charge my pack 24 hours every 3-4 months or when my IMA light comes on. I'm closing in on 130,000 miles and 18 months using this system. As far as I know my battery is original.
    8. My total cost was less than $200.

    Check out these sites for more: and ndex9.html.

    My solution applied everything I learned about Civic Hybrid to my Accord Hybrid. Unfortunately, little grassroots support exists for the HAH because it's a luxury model only made for 3 years. The HCH is much less expensive and still in production. Good luck with your HAH's
  • can you give me more info on who you called and what else you had to do to get this huge discount? any information would help. thanks
  • nosrocnosroc Posts: 1
    Sclass... How about an update on how your system is working. I'm intrigued by your solution and hope it might work for me
  • I love everything about this car but the ANC problem. Other than that, it was been a terrific car. But I (and my passengers) know every single time the engine is at or near 1500 rpms -- which is constantly around town, needless to say. Perhaps it's getting worse because the car is older. It's SO ANNOYING. I an angry at Honda that they don't do a recall on it, and when it's time to buy a new car, I'll be looking at Hundais because of it. Too bad!

    Thank heaven for this forum!!!
  • I would like to provide you with an answer to your ANC problem. I fixed mine in about an hour. Under the steering column there is a grey thing that holds 8-10 wires. There is a red and green one some are like a candy cane look, some sorta of checkered. Either way, it is red and green. You will cut it and then attach a wire to it with a connector and ground it out to the post. No more A/C problems and the parts cost $6. Don't go randomly cutting wires though.

    This Asian man saved me $850. At first I thought it was skipping steps, when I realized he really did show where everything was on it.
  • There are some states that have 10/150.000 Most are 8/80,000. You will know cause in your manual it will read PZEV which means you have the 10/150,000 warranty.
  • vegasbcvegasbc Posts: 1
    edited September 2013
    I have that same problem with my '05 HAH. I got in an argument with the dealership service dept because they couldn't duplicate the sound when they drove the car, even though Honda had a bulletin out about this problem. I eventually found the fix on a HAH forum which is:

    If your harmonic drone sound is most apparent between 1500 and 1700 RPM try this.
    1. Accord Hybrids with Navigations system: Turn the ignition switch to ACC (1) or ON (II)
    2. Turn the Audio Unit off. (Radio on and Off button, push to off)
    3. While holding down the upper part of both the "CH/DISK" and "SEEK/SKIP" buttons simultaneously, press the VOL/Pwr knob.
    This will place it in Diagnostic mode...DIAG will appear in the upper window above the Nav unit.
    Now while the engine is stopped and while in DIAG mode, turn the ANC ON and OFF by pressing the SCAN Button, you may have to push SCAN button ON and Off a couple times... While in the OFF mode, This will be displayed in the upper window above the Nav unit..... a low frequency hum (50HZ should be heard. While this low frequency tone is sounding turn the engine on and the sound should go away. IF it does your ANC is working and now is reset to the on position automatically. Now drive your car and see if the low frequency drone is gone!

    If you do not have the NAV unit follow this procedure.
    1. Turn the ignition switch to ACC (1) or ON (11)
    2. Turn the audio unit ON.
    3. While holding down both the "Preset1" and "Preset6" buttons simultaneously, press the AUDIO PWR knob.
    4. "DIAG" will appear on the audio unit display to indicate you have entered the self-diagnostic mode.

    NOW, while in Diag mode turn the ANC ON to OFF by pressing the #1 button, A LOW
    frequency hum (50HZ) should sound for up to a minute. While this low frequency HUM is Sounding turn the engine on and the HUM should GO AWAY. Now drive your car and see if the low frequency drone has gone away!

    There have been numerous cases where the ANC appears to toggle off all on its own.
  • Thanks for writing that all out... I'll try it tomorrow. Mine is almost more of a vibration than a sound. It's really a nuisance. Such a shame on a really nice car!

    I have 120,000 on the car now and am wondering if it's time to have the struts looked at. I asked at my local garage and they want $1,600 for all 4. GULP. Is that realistic? Gosh, I hope not!!!
  • soocitysue, we had the same issue but had the car in for the issue several times while under warranty but were never able to fix the issue. When we went to trade the vehicle in they tried to deduct the repair cost from the trade-in price after a test drive. When I asked what the repair was I was told the issue was with the air handling system and it would need to be replaced. Great. We decided to keep the car. The noise was our main reason for getting rid of the car. The dealer researched our files to show where we've been bringing the car to them since 2009 for this issue and they agreed to fix it for free. I hope this helps.
  • Does anyone have or know where I can obtain the specifications to the HAH battery pack? I want to make my own grid charger, but I don't have any information on the batteries, what is the maximum voltage they can be charged to, how many cells/sticks the pack holds, how many individual cells/batteries are in each stick, what are their voltages etc. Without this information, I am afraid to try and grid charge as I don't know what is the max voltage and amperage I should be setting the charger to. I really wish someone who has built a grid charger for the Accord Hybrid had taken the time to document the process, details, connections so that those of us catching up can follow in their footsteps. I am frustrated with the lack of support for our car as it applies to DIY charging/refreshing of the battery.

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