How to Read Your ECM or PCM Part Number (Ford, GM, Chrysler, Toyota, Honda, Nissan)

You have pulled the module out, found the sticker, and now you are looking at something like 6L2A-12A650-CAA or 68150638AC or 23710-ZN65A. This guide explains what those numbers mean, which parts of them matter, and which parts you can safely ignore.

Ford

A Ford service number looks like 6L2A-12A650-CAA and breaks into three parts.

• 6L2A – the prefix. The first character encodes the decade and year, the rest identifies the vehicle line.
• 12A650 – the base part number. This is Ford’s code for the engine control module, and it appears on every PCM regardless of vehicle.
• CAA – the suffix, which identifies the specific calibration.

You will also find a catch code on the label, usually a short alphanumeric like TVY1 or HFY6, and a separate hardware code in the 12B684 family. On Super Duty trucks there is additionally a strategy code, and it is printed on the connector rather than the module casing. Write down everything you can read.

Chrysler, Dodge, Jeep and Ram

Chrysler group numbers look like 68150638AC or 05150588AA, and there are usually two of them on the same module.

• The service number – typically an eight digit number starting 68, 04 or 05, followed by two letters.
• The generic number – a second number, often beginning 0515, which covers a broader range of vehicles.

The important thing to understand here is the suffix letters. On Chrysler group modules, AC, AD, AE and so on indicate the calibration revision, not a different part. A module ending AD will generally replace one ending AC on the same vehicle. Buyers routinely believe they need an exact letter match and pass over the correct part.

General Motors

GM uses plain eight digit numbers such as 12586242, with no letters.

You will often see two: a service number and a generic number like 12583660. There is also frequently a three or four character broadcast code such as YFXL or YFXM, which is what many people read off the sticker without realising it is not the part number.

GM modules are widely shared. The 12586242, for example, covers Silverado, Sierra, Tahoe, Suburban and Yukon across several years and four different engine sizes. A number matching a different vehicle than yours is not necessarily wrong.

Toyota and Lexus

Toyota numbers look like 89661-06G14. The 89661 prefix denotes the engine control module; the segment after the dash identifies the specific application.

Toyota is the make where exact matching matters most. Unlike Chrysler, a different suffix on a Toyota module generally will not work correctly, even on the same year and engine. Toyota also splits by build location – US built versus Japan built – and by Federal versus California emissions. The eighth character of your VIN identifies the engine, and the emissions label under the bonnet identifies the standard.

Honda and Acura

Honda uses a three part format like 37820-RNA-A61.

• 37820 – engine control module
• RNA – the engine and chassis family
• A61 – the specific calibration

Honda splits calibrations by transmission type and by drive type. On the Pilot, for example, the front wheel drive and all wheel drive modules carry different suffixes for the same year and engine.

Nissan and Infiniti

Nissan numbers look like 23710-ZN65A, where 23710 denotes the engine control module.

Nissan modules also carry a second code on the sticker in the MEC or JA families – for example MEC120-180 B1 or JA56P78 E01. Many owners only ever see this one, because it is often printed more clearly than the 23710 number. Both are usable for identification.

Nissan does not interchange between Federal and California emissions vehicles.

Hyundai and Kia

Numbers look like 39110-2G330 or 39100-2GBC1. The 391xx prefix denotes the engine control module.

These makes split by transmission type, emissions standard, drive type and sometimes build date. The 2001 Santa Fe, for instance, uses different modules either side of a September 2000 build cut-off.

What to do with your number

Type it into our ECM and PCM part number lookup, which covers close to two thousand modules and searches by part number, make, model or year.

If the sticker is unreadable – which is common on modules that have been sitting in an engine bay for fifteen years – send us your 17 character VIN instead. That identifies the vehicle precisely and we can work back to the correct module from there.

Still stuck?

Call 516-494-7838 with whatever numbers you can read, or your VIN, and a technician will identify the part for you before you order anything.