CAT Engine 26046 Fault Code: Cylinder #2 Injector Actuator #2:Current Above Normal
Also called Cylinder #2 Injector Actuator #2 - Current Above Normal, Cylinder #2 Injector Actuator #2 : Current Above Normal
Cylinder #2 Injector Actuator #2:Current Above Normal · ai-assisted, editor-reviewed · Last updated 2026-07-13
TL;DR
CAT code 26046 (SPN 3660, FMI 6) means the ECM detected high current flow through the Cylinder #2 injector actuator #2 solenoid circuit. The ECM disables that solenoid circuit to prevent damage and periodically retries firing it. This affects C13, C15, C18, C27, and C32 engines with Electronic Unit Injectors.
High severity. A disabled injector solenoid means Cylinder #2 is not firing correctly, which causes rough running, power loss, and potential misfire damage over time. It is not an immediate stop-the-engine emergency, but it should be diagnosed before continued heavy-load operation.
What does CAT Engine error code 26046 mean?
>Each fuel injector on these Electronic Unit Injector (EUI) engines has two solenoids. The ECM fires each solenoid with a 105-volt pulse timed precisely for engine load and speed. The ECM also watches the current flowing through each solenoid circuit as a way of confirming the pulse actually did its job.
When the ECM sees current flow that is too high on the Cylinder #2 injector actuator #2 circuit, it sets this code and shuts that solenoid circuit off to protect the wiring and driver electronics from damage. The ECM does not give up permanently. It periodically re-tries firing the injector, and if the short circuit condition is still there, the code sets again and the cycle repeats.
Because the ECM is actively disabling the circuit, the practical effect is a misfiring or non-firing cylinder, which shows up as rough idle, loss of power, and possibly a derate depending on how the engine is configured.
Common causes of 26046
- Damaged, corroded, or chafed connectors or wiring at the injector solenoid circuit
- An open or intermittent connection in the wiring harness between the ECM and the injector connector
- A fault in the harness between the ECM and the valve cover base, or in the harness under the valve cover itself
- An electronic problem with the injector solenoid itself, requiring injector replacement
- An intermittent wiring problem that only shows up when the engine is warm and under vibration from heavy load
- A faulty ECM (least common cause, checked only after wiring and injector are ruled out)
How to troubleshoot CAT Engine 26046: first checks
- Run or warm the engine to normal operating temperature before testing, since these faults typically appear once the engine is warm and under load or vibration
- Inspect all connectors and wiring on the Cylinder #2 injector circuit for corrosion, loose pins, chafing, or heat damage, paying close attention to connections near the valve cover base and under the valve cover
- Wiggle-test the harness and connectors while watching for the code to reset, since intermittent faults often only appear under vibration
- Check the harness between the ECM and the injector connector for continuity and confirm there is no open circuit
- If wiring and connectors check out, test or swap the injector to determine if the injector solenoid itself is faulty
- Only after ruling out wiring, connectors, harness, and injector should the ECM be considered as the cause
How the code clears
No separate clearing step is listed. Once the wiring, connector, harness, or injector problem is repaired, the ECM should stop detecting high current on the circuit and the code should not reset on its own. If the code returns after repair, the fault has not been fully resolved.
Affected models and serial ranges
26046 appears in our records across 5 CAT Engine models. Match your machine by model and serial number.
| Model | Serial ranges |
|---|---|
| C13 | Serial range not listed in source records |
| C15 | Serial range not listed in source records |
| C18 | Serial range not listed in source records |
| C27 | Serial range not listed in source records |
| C32 | Serial range not listed in source records |
Frequently asked questions
What does CAT code 26046 mean?
It means the ECM detected current above normal (a short-circuit-type condition) on the Cylinder #2 injector actuator #2 solenoid circuit and disabled that circuit to prevent damage, while continuing to periodically try firing the injector.
Which CAT engines can set code 26046?
C13, C15, C18, C27, and C32 engines equipped with Electronic Unit Injectors (EUI) can set this code.
Can I keep running the engine with this code active?
The engine will likely run rough and lose power on that cylinder since the ECM has disabled the injector solenoid circuit. It's best to diagnose and repair the issue rather than continue heavy-load operation, since the ECM will keep repeating the disable-and-retry cycle if the short remains.
Why does this fault often show up only when the engine is warm?
Wiring and connector problems, along with vibration from heavy engine loads, often only cause a short or open circuit once components have heated up and expanded, or once vibration shakes a marginal connection loose. That is why testing should be done at normal operating temperature.
Is this a wiring problem or an injector problem?
It can be either. Damaged or corroded connectors and wiring, an open in the harness between the ECM and the injector, or a fault in the harness near the valve cover are common causes. If those check out fine, the injector solenoid itself may be faulty. A bad ECM is possible but is the least common cause.
Does the ECM permanently shut off the injector once this code sets?
No. The ECM disables the solenoid circuit to prevent damage from the high current, but it periodically tries to fire the injector again. If the short circuit condition is still present, the code will set again and the disable-and-retry sequence repeats.