Bobcat M0422 (04-22) Fault Code: Engine Oil Pressure Out of Range Low
Also shown on the panel as 04-22
Engine Oil Pressure Out of Range Low · ai-assisted, editor-reviewed · Last updated 2026-07-13
TL;DR
Bobcat fault code M0422, shown on the panel as 04-22, sets when the gateway controller sees a voltage below 0.4 volts for 30 seconds on the engine oil pressure sensor signal wire (wire 3140 or wire 3520 depending on model/harness). The sensor runs on a 5.0 volt supply, so a reading that low almost always points to a wiring, connector, or sensor problem rather than a genuine oil pressure drop, but it should never be assumed safe until checked.
High severity. This code deals with engine oil pressure reporting. A false low reading is common, but if actual oil pressure is low the engine can suffer serious damage in a short time. Treat every M0422 as a stop-and-check situation until you confirm whether it's a wiring fault or a real pressure problem.
What does Bobcat error code M0422 mean?
M0422 is Bobcat's fault code for 'Engine Oil Pressure Out of Range Low.' It is generated by the gateway controller, which constantly monitors the voltage signal coming from the engine oil pressure sensor. This sensor runs on a 5.0 volt supply and its signal wire is either wire 3140 or wire 3520, depending on the machine and harness variant.
The controller sets M0422 when it sees the signal voltage drop below 0.4 volts and stay there for 30 seconds while the key switch is in the run/enter position. That sustained low voltage tells the controller either that oil pressure has actually dropped to a dangerously low level, or that the sensor circuit itself has failed in a way that mimics a low-pressure signal.
Because engine oil pressure protects nearly every moving part inside the engine, this code is treated seriously even though many cases turn out to be a wiring or connector issue rather than an actual lubrication problem.
What triggers a Bobcat M0422 code?
The gateway controller sets M0422 when it detects a voltage below 0.4 volts on the engine oil pressure sensor signal wire (wire 3140 or wire 3520) for a sustained 30 seconds, with the key switch in the run/enter position. The sensor's supply voltage is 5.0 volts.
Common causes of M0422
- The 5 volt supply wire (wire 5140 or wire 3500 depending on model) or the signal wire (wire 3140 or wire 3520) is shorted to ground or has an open circuit.
- The engine oil pressure sensor itself has failed.
- The gateway controller has an internal fault.
- Moisture, corrosion, or pushed-back pins in the gateway controller connectors, the engine oil pressure sensor connector, or the mainframe harness.
- An intermittent fault: loose connections, corrosion, pushed-back pins, the controller, the wire harness, or a combination of these problems that may not be found unless the code is actively present during testing.
How to troubleshoot Bobcat M0422: first checks
- Before anything else, check actual engine oil level and condition on the dipstick. Confirm there isn't a genuine low oil pressure condition before assuming it's electrical.
- Inspect the engine oil pressure sensor connector and the gateway controller connectors for moisture, corrosion, or pushed-back pins.
- Visually trace the signal wire (3140 or 3520, depending on your model) and the 5 volt supply wire (5140 or 3500) for chafing, pinches, or shorts to ground, especially where the harness runs near the engine or mainframe.
- With the key switch in run/enter, check the voltage at the sensor connector to see if it matches the expected 5.0 volt supply and whether the signal stays below 0.4 volts continuously or only intermittently.
- If the code is not active during testing, wiggle-test the harness and connectors near the sensor and gateway controller, since intermittent connection problems (loose pins, corrosion) will not show up on a static check.
- Swap or bench-test the engine oil pressure sensor if wiring and connectors check out, since sensor failure is a listed possible cause.
How the code clears
This code is self resetting. No separate clearing step is listed. Once the underlying wiring, connector, or sensor issue is repaired and the voltage signal returns to a normal range, the code should clear on its own during normal operation.
Affected models and serial ranges
M0422 appears in our records across 16 Bobcat models. Match your machine by model and serial number.
| Model | Serial ranges |
|---|---|
| S510 | SN A3NJ11001-99999, SN A3NK11001-99999, SN ATZC11001-ATZC99999 |
| S530 | SN A7TV11001-99999, SN ATZD11001-99999 |
| S550 | SN A3NK11001-A3NL99999, SN A3NM11001-99999 |
| S570 | SN A7U711001-799999, SN A7U811001-899999 |
| S590 | SN ANMN11001-99999, SN ANMP11001-99999 |
| S630 | SN A3NT12370-99999, SN A3NU11001-11111, SN A3NU11112-99999 |
| S650 | SN A3NV11001-13098, SN A3NV13099-99999, SN A3NW11001-11248, SN A3NW11249-99999 |
| S750 | SN A3P211001-299999 |
| S770 | SN A3P411001-99999 |
| T550 | SN A7UJ11001-AJZV12276 |
| T590 | SN ALJU11001-999999, SN B37811001-999999, SN B3Z711001-999999 |
| T630 | SN A7PU11001-11663, SN A7PU11664-99999 |
| T650 | SN A3P012214-099999, SN A3P111242-199999 |
| T750 | SN ANKA11001-A99999 |
| T770 | SN A3P811001-899999, SN A3P911001-999999 |
| T870 | SN A3PG11001-99999, SN A3PH11001-99999 |
Frequently asked questions
What does Bobcat code M0422 mean?
It means the gateway controller detected the engine oil pressure sensor signal voltage drop below 0.4 volts for 30 seconds, which the controller reads as 'oil pressure out of range low.' It can be a real low oil pressure condition or a wiring/sensor fault.
Is M0422 safe to keep driving or working with?
No. Because this code can indicate an actual drop in engine oil pressure, it should be treated as a stop-and-check condition. Continuing to run the engine with genuinely low oil pressure can cause serious internal damage within minutes.
What wires are involved in M0422?
Depending on the machine and harness version, the signal wire is either wire 3140 or wire 3520, and the 5 volt supply wire is either wire 5140 or wire 3500. Both wires should be checked for shorts to ground or open circuits.
Will M0422 clear itself after I fix the problem?
Yes. This code is self resetting. There is no separate manual clearing procedure once the wiring, connector, or sensor issue causing the fault has been repaired.
Can a bad connector cause M0422 even if the sensor is fine?
Yes. Moisture, corrosion, or pushed-back pins in the gateway controller connectors, the sensor connector, or the mainframe harness are all listed as possible causes, and these can produce the same low-voltage signal as a failed sensor.
Why does the code sometimes disappear before I can diagnose it?
If the fault is intermittent, such as a loose connection or corrosion that only causes a problem occasionally, the code may not be present when you test the circuit. In these cases the root cause may require a wiggle test or extended monitoring to catch it in the act.
Which Bobcat models can show M0422?
This code applies across a range of Bobcat loaders and compact track loaders, including the S510, S530, S550, S570, S590, S630, S650, S750, S770, T550, T590, T630, T650, T750, and T770 models.