Owners of other Acura or Honda vehicles such as the RDX, ILX, TLX, RLX, TL, CL, RSX, RL, TSX, ZDX, NSX, Integra, Pilot, Accord, Civic, Fit, Clarity, CR-V, CR-Z, HR-V, Odyssey, Element  and Ridgeline with the VTEC 3.5L V6 engine may also find these DIY instructions to be helpful.

The original "OEM" alternator is part number Denso 210-0580 (also known as part # 2100580).

The tools needed to complete this procedure include a flathead screwdriver, a 10mm socket with a 1/4" drive ratchet, a 12mm socket with a 3/8" drive ratchet and a 14mm socket with a long 18" or 24" 1/2" drive breaker bar to release the serpentine belt.

Here are a few other compatible replacement alternators with their part numbers: TYC 2-11151, DB Electrical AND0339, Bosch AL1297X, Remy 12723, Discount Starter & Alternator 11151N, ECCPP AND0339, Quality Rebuilders 11151 and the Acura 31100-RJA-A02.

To test your old alternator and battery before purchasing any new parts, I recommend using a digital multimeter tool.

Place the leads of the multimeter on the 12V battery with the engine off. The voltage should be just above 12V such as 12.2V or 12.3V (unless you were driving around with a failing alternator and the battery light lit up on the dash for many miles).

Then start the engine and check the multimeter again. If the alternator is working properly the voltage should be anywhere from above 13V to just over 14V. If the voltage with the engine running is well below 13V, the alternator is failing and should be replaced.

While you are replacing the alternator, I recommend charging the 12V battery with a Battery Tender. I like to attach my Battery Tender Jr. to our car batteries at least once a month to fully charge them since we tend to drive many short trips that can drain the battery and not allow the alternator enough time to fully charge them again.

I didn't want to risk breaking the plastic handle while removing or installing the alternator.

Set the dipstick aside in a safe place.

Push a small clean towel or rag into the dipstick port to keep debris from falling into the engine.

For better access to the alternator, you'll need to release the power steering reservoir and the coolant overflow bottle.

Lift the P/S reservoir bottle straight off its mounting bracket.

Do not disconnect the hoses.

Then lift the white translucent plastic coolant overflow bottle straight off its mounting bracket.

Next, move to the 12V automotive battery on the right (driver) side of the engine bay.

Pull the negative terminal straight off the "-" battery post.

Wrap the terminal in a small towel and tuck it away on the side of the battery to help prevent accidental electrical contact.

Pull the large black rubber boot off the main output B+ connector and terminal.

Set the 12mm nut aside in a safe place.

Pull the output cable off the B+ terminal stud.

Slide back the grey rubber dust boot to expose the green plastic connector.

Try to avoid using excessive force. The regulator connector should slide out relatively easily.

Loosen the 10mm bolt that secures the bracket in place by turning it in the counterclockwise direction.

Set the 10mm bolt aside in a safe place.

Gently pull back the release tab and lift the wire loom off the bracket.

Move the B+ output cable to just below the cowl and behind the electrical fuse box.

Once both of the electrical cables are safely out of the way, you can move on to releasing the serpentine accessory belt.

Attach the 14mm socket to an 18" or 24" long 1/2" drive breaker bar.

Place the socket over the bolt head on the tensioner pulley located behind the alternator, below the power steering pulley and just above the small idler pulley.

Firmly lift the breaker bar handle and rotate it back towards the firewall to release the tension on the belt.

Avoid placing your fingers in between the belt and any of the pulleys.

Move the serpentine belt back away from the alternator. If you aren't planning on replacing the serpentine belt, try to avoid pulling it off the other pulleys to save yourself time later on.

Next, locate the black metal bracket on the top of the alternator and the two 12mm bolts that hold it into place.

The rear 12mm bolt is attached to the engine's cylinder block.

Loosen the front bolt by turning it in the counterclockwise direction with a 12mm socket and a 3/8" drive ratchet.

Do not fully remove either bolt.

Move to the rear bottom corner of the alternator and locate the larger 14mm bolt.

Then remove the two 12mm bolts on the top of the alternator.

The slightly longer silver metal 12mm bolt is attached to the top of the alternator on the front of the black metal bracket.

The shorter bronze / copper / gold colored bolt is attached to the engine block on the rear of the black metal bracket.

I was able to easily lift the old alternator out of the engine bay.

If you have trouble lifting out the old alternator, you may need to use a pry bar to loosen it from the lower mounting bracket.

So I purchased the OEM quality Denso 210-0580 remanufactured alternator. I'm hoping it will last at least another 150,000 miles.

Push the "ear" at the bottom of the new alternator into the mounting bracket and line up the bolt holes.

Spin in the long 14mm bolt into the bottom of the alternator a few turns in the clockwise direction by hand to prevent it from becoming cross thread.

I had labeled the correct orientation of the black metal bracket on a paper towel.

Spin in the longer 12mm silver metal bolt into the front of the bracket and through the alternator.

Then spin in the shorter bronze colored 12mm bolt into the hole on the rear of the bracket and into the cylinder block.

Starting the bolts by hand will help prevent them from becoming cross threaded.

(If you would like to tighten the bolts with a torque wrench, the service manual values are as follows: 14mm bolt - 33 lb-ft and two 12mm bolts - 16 lb-ft of torque.)

Place the 14mm socket over the tensioner pulley with a long 1/2" drive breaker bar.

Rotate the breaker bar or ratchet handle back towards the windshield.

Carefully slip the serpentine belt over the alternator pulley.

I included a serpentine accessory belt routing diagram just in case you need to re-route the belt over the other pulleys as well.

Spin on the 12mm nut a few turns by hand in the clockwise direction.

Tighten the nut in the clockwise direction with the 12mm socket and a 3/8" drive ratchet until it is snug.

If you live in a very humid climate, you may choose to apply some dielectric grease to the B+ terminal and ring connector to help prevent corrosion (rust) and ensure a reliable electrical connection.

Next, route the external voltage cable back into place.

Locate the brown plastic socket on the right (driver) side of the alternator.

The release button should be situated at the front of the connector facing towards the radiator.

Slide the grey rubber cover over the voltage regulator electrical connector.

Push the purple pop rivet wire loom retainer back into the hole on the black metal bracket attached to the output cable.

Tighten the 10mm bolt in the clockwise direction until it is snug.

Re-attach the retaining clip for the output cable to the bracket near the power steering pump pulley.

Double check that the two electrical cables are properly routed. They should be clear of all the pulleys and serpentine belt.

It should "click" securely into place.

Then push the coolant overflow bottle down into its mounting bracket.

Pull the small towel out of the oil dipstick port.

Push the oil dipstick back into place.

Push the negative terminal back on to the "-" battery post.

Tighten the 10mm terminal nut by turning it in the clockwise direction until it is snug.

Try to avoid over tightening the terminal nut to prevent from damaging the battery post which could lead to an acid leak.

On some Acura or Honda models, the radio security code will be on a white sticker attached to either the inside or outside of the glove box. Our MDX has a anti-theft radio code card inside the leather binder that contains the owner's manual.

Turn the ignition switch to the "ON" position but do not start the engine. You should see "CODE" displayed on the radio.

Enter the security code into the radio by using the numbered preset radio station buttons "1, 2, 3, 4, 5, 6".

To test that the new alternator is working properly, connect the multimeter leads to the battery with the engine running. The voltage should be anywhere from just above 13 volts to just over 14 volts.

Be sure to record the alternator change in your vehicle's service records.

For more, please check out all of my 2001-2006 Acura MDX DIY Repair & Maintenance Guides.