On Caterpillar machines β excavators, loaders, bulldozers, or gensets β the ECM (Engine Control Module) plays a central role. It manages injection, engine regulation, sensors, and even some hydraulic functions.
But when this electronic brain malfunctions, the symptoms can be varied, and diagnosing the issue becomes a real puzzleβ¦ unless youβre properly equipped.
π Thatβs where Jaltest INFO Web OHW makes a real difference: this online software gives you access to Caterpillar-specific technical data and guides you through ECM fault diagnosis and resolution β in record time.
Common symptoms of a faulty Caterpillar ECM
These are the most frequent issues reported by CAT machine users:
- Check Engine light stays on
- Engine slows down without hydraulic pressure loss
- Engine stuck at low or high RPM
- Intermittent injection problems
- No communication with the ECM via diagnostic tool
In about 60% of cases, the issue is caused by a misread sensor or a software fault in the ECM β not a mechanical failure.
How does Jaltest INFO Web OHW help diagnose a Caterpillar ECM?
β 1. Identify Caterpillar ECM fault codes
Examples:
- E-ID:190-3 β Intake air temperature sensor: low voltage
- E-ID:111-1 β Low ECM supply voltage
- E-ID:232-2 β CAN communication fault between engine ECM and hydraulic ECM
π‘ In Jaltest INFO Web OHW: enter the fault code β get a description, likely causes, and step-by-step solution.
β 2. Access complete Caterpillar ECM wiring diagrams
With interactive views, you can:
- Locate the ECM on specific machines (e.g. 320D, 950H, D6Rβ¦)
- Identify each connector, pinout, and expected voltage
- Trace connections between sensors, power supply, and ECM
π― Result: You test the right components without unnecessary disassembly.
β 3. Follow Caterpillar ECM-specific test procedures
Jaltest INFO Web OHW provides guided sheets to:
- Check electrical continuity between pins
- Test ECM power supply (9β32V depending on model)
- Measure sensor input values at the ECM
- Reset or recalibrate parameters after repair
β 4. Get a list of ECM-compatible CAT sensors
The software also provides:
- OEM references
- Normal operating values (range in V, ohms, Hz)
- Tolerances based on temperature or engine load
Example:
Fuel Rail Pressure Sensor
β Expected value (engine running): 28,000β35,000 kPa
β Voltage: 0.5 V (idle) to 4.5 V (full throttle)
π§ͺ Real-life case: ECM fault on Caterpillar 320D excavator
π§ Symptoms: Check engine light + unstable idle + fault code E-ID:94-1
π§ Diagnosis with Jaltest INFO Web OHW:
- Fault code read
- Engine RPM sensor test β OK
- ECM power supply test: 7.6 V instead of 12 V β ground issue
π§ Fix: Connector cleaned, fuse replaced, fault code cleared β normal operation restored
Direct benefits for your Caterpillar workshop
Before Jaltest INFO Web | With Jaltest INFO Web OHW |
Blindly searching for diagrams | Instant, precise schematics |
Trial-and-error sensor testing | Clear, guided procedures |
Diagnosis time: >2 hours | Average time: 30 minutes |
Risk of wrong diagnosis | Reliable, multi-model data |
Dependent on scan tool | Usable even without interface |
β Conclusion: ECM faults wonβt catch you off guard anymore
With Jaltest INFO Web OHW, you have everything you need to work confidently and efficiently on Caterpillar ECM issues.
β Save time
β Avoid unnecessary part replacements
β Reduce stress on the jobsite
π Request your free trial now in just a few clicks:
π https://agridiaginfo.co.uk/