B2BEmersonEIMS serves commercial, industrial, healthcare, telecom, hospitality, government & contractor clients.• Engineering-led • SLA-backed • Documented commissioning
Diesel engine fault codes for excavators, loaders, rollers, telehandlers, compressors and drill rigs — the same engines that power them power gensets, and the codes are the same.
2,155 verified codes across 11 engine brands and 53 engine families. Every one is checked. Plus a SAE J1939 decoder — 42 verified SPNs and all 23 defined FMIs — which reads John Deere, JCB, Komatsu, Doosan and Volvo engines from the standard. We publish no invented codes and no invented fixes.
J1939 is an SAE standard, so an SPN/FMI pair means the same thing on a John Deere, JCB, Komatsu, Doosan or Volvo as on any other engine — even though we hold no manufacturer table for those makes.
A fault code comes from the engine ECM, so it belongs to the engine, not to the paint on the bodywork. The same Perkins 1104 sits in machines wearing several different badges, and two machines from one manufacturer can carry completely different engines depending on year and market.
So we do not ask what the machine is. Find the engine data plate — usually on the rocker cover, the block above the starter, or the timing case — and read the make and model from it. Search that, plus the number on the display. It is the answer that is always right for the machine in front of you.
Fault code numbers are industry-standard identifiers used for identification only. Descriptions, causes and checks are written in our own words as statements of engineering fact — nothing here is transcribed from a manufacturer service manual. This tool is not affiliated with or endorsed by any manufacturer, and all brand and model names are the property of their owners. For official documentation, always use the manufacturer's manual for the specific engine.
Most fault-code sites imply they cover everything and return nothing. Here is the real list, with counts.
| Engine brand | Codes | Engine families |
|---|---|---|
| Caterpillar | 547 | 3500 Series, C12, C13/C15/C18, C15, C18, C7, C9, EMCP 3 Series, EMCP II Series, EMR3, TCD 3.6 L4 |
| Perkins | 520 | 1100 Series, 1200 Series, 1500 Series, 2000 Series, 400 Series, 4000 Series, All Models, Evolution Series, Various |
| Cummins | 500 | ISX Series, QSB Series, QSC Series, QSK Series, QSL Series, QSM Series |
| Deutz | 252 | EMR3, EMR4, TCD 2.9, TCD 3.6 L4, TCD 7.8, TELYS1 |
| SDMO | 118 | APM303, APM403, MICS Telys, Model, TELYS1 |
| Atlas Copco | 75 | QAS Series, QEP Series, QES Series, WP Series |
| Weichai | 45 | All Models, WP Series |
| Generac | 30 | 2 Cylinder Units, 5500, Single Cylinder Units, Various |
| Cummins Onan | 26 | 10RESV and 12RESV, 14RES/RESL and 20RES/RESL, Various |
| Kohler | 24 | 14RES/RESL and 20RES/RESL, C13/C15/C18 |
| Doosan | 18 | DS4100 |
We hold no maker-specific fault table for:
John Deere · JCB · Komatsu · Hyundai · Volvo CE · Kubota · Yanmar · Sany · XCMG · LiuGong · Lonking · Shantui
That does not leave you stuck. All of them speak SAE J1939, where a fault is an SPN saying which parameter is at fault and an FMI saying how it failed — and both mean the same thing on a John Deere as on a Cummins. We hold 42 verified SPNs and all 23 defined FMIs, so the decoder above reads those machines from the standard rather than guessing at them.
Two honest limits. Manufacturer-proprietary SPNs sit outside the standard ranges, differ between makers, and are not included — the decoder says so rather than offering a near match. And many of these machines run engines we cover outright (Perkins, Cummins, Deutz, Weichai), so check the engine plate first. If you have the workshop manual for anything on this list, send it and we will add it properly.
A code tells you what the ECM detected, not always what failed. Our mobile workshop covers all 47 counties and carries diagnostic equipment for engine, ECU and hydraulic faults.