Isuzu Key Fob Battery Replacement: CR2032 for D-Max, MU-X, Ascender, Rodeo and Trooper Keys
Isuzu keys take one CR2032 battery: the separate remotes on the 1998 to 2004 Rodeo, Trooper and Axiom, the GM-built remotes on the 2003 to 2008 Ascender and i-Series pickups, the flip key on the 2012 to 2020 D-Max and MU-X, and the smart key on the current D-Max and MU-X. Open a separate remote or flip key at the notch on the seam; open a smart key by pulling out the emergency blade and levering at the slot. Fit the new cell the same way round as the old one. No reprogramming is needed. A few early Rodeo and Trooper remotes take a thinner CR2025, so read the code on the old cell before you buy.
Isuzu is an odd case. In North America the brand stopped selling passenger vehicles in 2009, and its last models were rebadged General Motors trucks with GM keys. Everywhere else the D-Max pickup and MU-X SUV are current vehicles with their own flip key and, since 2020, a smart key. The good news is that all of them take the same CR2032 coin cell, so the only thing you need to get right is where each key opens. This guide covers both the old North American models and the current D-Max and MU-X, and what to check if the vehicle still does not see the key afterwards.
Which battery your Isuzu key fob takes
Find your key in the table. The FCC ID or part number printed on the back of the fob tells you which family it belongs to.
| Key style | Typical FCC ID or part number | Common on | Battery |
|---|---|---|---|
| Separate remote on the key ring, Isuzu-built | HYQ1512A, LHJ002, 8-97200-xxx | Rodeo and Rodeo Sport 1998 to 2004, Trooper 1998 to 2002, Axiom 2002 to 2004, VehiCROSS, Amigo | CR2032 on most; a few early remotes take a CR2025, so read the old cell |
| Separate remote, GM-built | KOBLEAR1XT, 15913421, OUC60270 | Ascender 2003 to 2008, i-280, i-290, i-350 and i-370 pickups 2006 to 2008 | CR2032 |
| Flip key (blade folds into the remote) | 8-98xxxxxx, 2012 to 2020 D-Max key | D-Max 2012 to 2020, MU-X 2013 to 2020, N-Series trucks with remote | CR2032 |
| Smart key with push-button start | 2020 on D-Max and MU-X key | D-Max 2020 on (higher trims), MU-X 2021 on | CR2032 |
The code stamped on the flat + face of the old battery is the final word. If you open the key and find a CR2025 in a D-Max, MU-X, Ascender or i-Series key, someone fitted the wrong cell last time; those holders are designed for the 3.2 mm thick CR2032 and a thinner cell makes poor contact. If the old battery is missing, the owner’s manual lists the type in the section on the remote control or keyless entry system.
The code tells you the size: the first two digits are the diameter in millimetres and the last two are the thickness in tenths of a millimetre, so a CR2032 is 20 mm wide and 3.2 mm thick while a CR2025 is the same width but thinner. A thinner cell in the same holder makes poor contact and causes the random dropouts people blame on the vehicle. Our key fob battery size chart lists every size by brand.
What you need
- One new CR2032 from a name brand (Panasonic, Energizer, Duracell, Murata or dealer branded all work)
- A small flat-blade screwdriver, a coin, or a plastic pry tool, and a small Phillips screwdriver for the older remotes
- A clean table and good light, so a dropped battery or the small rubber button pad does not vanish
Avoid rechargeable cells such as LIR2032. They have the right shape but a higher voltage, and they are not what the key is designed for. A branded 3 V lithium cell with a date well into the future is all you need.
Changing the battery in an Isuzu D-Max or MU-X key
This covers the 2012 to 2020 flip key and the 2020 and newer smart key. The flip key opens at the seam; the smart key opens from the emergency blade slot. Both take a CR2032.
On the flip key, press the button and fold the blade out. On the smart key, slide the small catch on the back and pull the emergency blade straight out; you will use its tip in the next step.
On the flip key, find the notch on the seam of the case beside the hinge or on the bottom edge, put a coin or flat screwdriver in it and twist. On the smart key, look into the slot the blade came from: there is a small notch between the halves. Push the tip of the blade or a flat screwdriver in and twist gently; the back cover lifts off from that end. Do not pry around the outside seam of a smart key.
Before you touch the battery, look at which side shows. The + side with the code printed on it normally faces up, towards the back cover, but take a photo so there is no guessing later.
Use a plastic tool or the tip of the blade at the small cut-out beside the battery to lever it up, and lift it out by the edge. Do not slide a metal tool across the circuit board.
Hold the new cell by its edges and press it into the holder the same way round as the old one. It should sit flat and click under the retaining tab. A battery that rocks or stands proud is the wrong size.
Snap the cover or halves back together until the seam is flush all round, fold or slide the blade home, and press lock and unlock. The lights should flash and the small LED on the key should blink with each press.
If the rubber button pad came away with the cover, lay it back in the front half first, buttons facing out, before you close the case. A pinched pad is why buttons feel mushy after a battery change.
Changing the battery in an older Isuzu remote
This covers the separate remotes on the Rodeo, Trooper, Axiom, Amigo and VehiCROSS, and the GM remotes on the Ascender and i-Series pickups. Nearly all take a CR2032.
- Turn the remote over. Some Isuzu-built remotes have a small Phillips screw in the back; remove it. Otherwise find the notch on the seam, on one edge or next to the key ring hole on the square GM remotes.
- Put a coin or the tip of a flat screwdriver in the notch and twist. Work the two halves apart slowly rather than forcing one spot; the plastic on these remotes is twenty years old and brittle.
- Note which way the battery faces, then lever it out from the cut-out at its edge. On the oldest remotes the cell sits under a small metal clip; lift the clip, do not bend it back.
- Press in the new cell the same way round, check the rubber button pad is seated, snap the halves together until the seam is flush all the way round, and refit the screw if there was one.
On a turn-key Isuzu the transponder chip, where fitted, is in the key itself and does not need the battery, so a dead remote never stops the vehicle starting; you just have to unlock the door with the key. If a GM remote has lost its sync after months without power, press and hold lock and unlock together for a few seconds while standing next to the vehicle; many of them re-pair that way.
3V lithium CR2032 coin cell
For D-Max, MU-X, Ascender, i-Series and most Rodeo and Trooper remotes. Buy a name brand in a small multi-pack and keep the spares in the glove box, not loose in the key.
Other size: CR2025
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Do you need to reprogram an Isuzu key after a battery change?
No. The pairing between the key and the vehicle is stored in memory that does not depend on the battery, so an Isuzu key keeps working as soon as a fresh cell goes in. If the instrument panel on a D-Max or MU-X showed a key battery warning, it clears after the next start or two. The only keys that sometimes need a nudge are the oldest GM-built remotes, which can lose sync after months without power; the lock-and-unlock hold described above fixes that.
If the vehicle still does not see the key
First, get moving. On a D-Max or MU-X with push-button start, hold the smart key with its buttons facing you and touch the Isuzu logo end of the key to the engine start button, then press the brake and press the button while holding it there; the button reads the chip in the key. On a turn-key Isuzu, the key works in the ignition regardless of the remote battery. The emergency blade opens the driver’s door if the remote lock does not respond.
Then work through the usual causes, in order of how often they turn out to be the problem:
- Wrong size. A CR2025 or CR2016 in a CR2032 holder makes patchy contact and the key works one day and not the next. Compare the code on the new cell with the old one.
- Upside down. If the key does nothing at all and the LED does not flash, open it and turn the battery over.
- Bent or dirty contact. The spring contact can be flattened by prying. Lift it gently with a plastic tool and clean it with a dry cotton bud. See how to clean key fob battery contacts.
- Tired new battery. Cells that sat in a drawer or came from an unbranded multi-pack can be flat out of the packet. Try a second one from a fresh pack.
- The vehicle’s 12 V battery. If the vehicle was also slow to crank or the dash lights were dim, the problem is the vehicle, not the key. See can a bad car battery cause key fob problems.
- Damage inside the key. A key that has been dropped hard, through a wash, or left on a hot dashboard can have a cracked solder joint or corroded board. A locksmith can test whether it still transmits.
If the buttons work but the vehicle does not respond, the full checklist is in key fob not working after a battery replacement.
What it costs
An Isuzu dealer or a locksmith will usually fit a battery while you wait for the cost of the cell plus a small labour charge. The larger figures only apply if the key itself has to be replaced. Old Rodeo and Trooper remotes are often cheaper to replace with a used unit than a new one, since the vehicles are no longer supported by dealers in North America; a locksmith who handles GM vehicles can usually sort an Ascender or i-Series remote.
How long the new battery will last
A separate remote or flip key only transmits when you press a button, so a CR2032 in one typically lasts three to five years. The D-Max and MU-X smart key listens for the vehicle and answers whenever you touch a door handle, so expect one to two years, less if the key lives within a few metres of the vehicle overnight. Heat, cold and carrying the key loose with things that press the buttons all shorten that. More detail is in how long key fob batteries last.
Safety: keep coin batteries away from children and pets
A swallowed coin cell can cause serious internal burns within hours. Keep spares and the old cell out of reach, and dispose of old batteries at a drop-off point rather than in household waste. If you think a child has swallowed a battery, go to the emergency room straight away and call the National Battery Ingestion Hotline at 1-800-498-8666, or Poison Help at 1-800-222-1222.
Frequently Asked Questions
Nearly every Isuzu key takes a single CR2032 3 V lithium coin cell: the D-Max and MU-X flip keys and smart keys, the GM-built Ascender and i-Series remotes, and most Rodeo, Trooper and Axiom remotes. A few early remotes take a CR2025, so confirm with the code on the old battery.
On the flip key, fold the blade out and twist a coin in the notch on the seam. On the smart key, slide the catch, pull out the emergency blade, and push its tip into the notch inside the slot it came from and twist. The back cover lifts off.
No. Isuzu keys keep their pairing without battery power. The key works as soon as the new battery is in. An old GM-built remote that has lost sync can be re-paired by holding lock and unlock together next to the vehicle.
Touch the logo end of the key to the engine start button, press the brake and press the button while holding the key there. The button reads the chip in the key. Use the emergency blade to unlock the driver’s door.
Only if the old cell was a CR2025. In a key designed for a CR2032 it is thinner, so the contact is poor and the key becomes unreliable. Match the code on the old battery.
Isuzu dealers in North America no longer stock them, so the usual route is a used remote with the same FCC ID or part number, programmed by a locksmith, or the on-board programming sequence in the owner’s manual where the vehicle supports it.