Short answer: the part number is printed on a sticker or stamped label on the module’s case. It’s usually the longest number on the label, and its format depends on the make. For an exact match, search that number, not the vehicle alone. Modules that look identical can be programmed or wired differently.
Why the part number matters more than year, make and model
One vehicle can use several versions of the same module, depending on engine, transmission, options, build date and software level. Two modules that fit the same car can have different part numbers and won’t swap. Matching the part number on your original module is the most reliable way to get the right replacement.
Where to look
- Engine and powertrain modules (ECM, PCM, ECU): usually under the hood near the battery, on the firewall, or behind the kick panel or glove box. The label is on top of or beside the case.
- Transmission modules (TCM): under the hood, under a seat, behind a kick panel, or built into the transmission itself.
- Body control modules (BCM): under the dash, behind the kick panel, or in the interior fuse box.
- ABS modules: attached to the brake hydraulic unit, usually near the master cylinder.
- Instrument clusters and radios: on a label on the back of the unit once it’s removed.
Take a clear photo of the whole label before you search. It’s often easier to read the photo zoomed in than the label itself.
Which number on the label to use
Labels often show several numbers: hardware, software or calibration, serial, and supplier numbers (such as Bosch, Continental, Delphi or Denso). The car maker’s part number is the one to search. Common formats:
- Ford, Lincoln, Mercury: a three-part number such as
AL3A-12A650-ABC. See Ford engineering vs service part numbers. - GM (Chevrolet, GMC, Buick, Cadillac): an 8-digit number such as
12654321. See GM module part numbers. - Chrysler, Dodge, Jeep, Ram: 8 digits plus two letters, such as
68123456AB. See Mopar part numbers. - Toyota, Lexus, Honda, Nissan and other Asian makes: five digits, then more characters, such as
89661-0C123or37820-RCA-A01. See Toyota, Honda and Nissan part numbers.
Tips for searching
- Search with and without dashes. We match both, but other sites may not.
- If the label is worn, search the part you can read and compare the results with your photo.
- Don’t search the supplier’s number (for example a Bosch number starting 0 261) unless that’s the only number you have.
Frequently asked questions
Can I find the module part number from my VIN?
A dealer parts department can look up the current service part number from your VIN. The number on your original module may differ, because many numbers have been replaced over the years. Either number can be searched.
The label is missing or unreadable. What now?
Email us your VIN, the module’s location in the vehicle, and a photo of the module. We’ll help you identify it.
Find your module
Search the part number from your module’s label on Module Mountain, or shop by vehicle. Every module is refurbished to order, ships free by USPS Priority in the USA, and is covered by our one-year warranty (exchange and warranty policy). Can’t find your number? Email contact@modulemountain.com with a photo of the label and your VIN.