Volvo EC210B LC Fault Code 142PSID99: Technical Guide

What is Volvo EC210B LC Fault Code 142PSID99?

Fault Code 142PSID99 indicates a communication error or data link failure within the machine's CAN (Controller Area Network) system, specifically related to Parameter Source Identifier (PSID) 99. This code typically signals that the Electronic Control Module (ECM) is unable to receive or validate data from a specific component or network node on the machine's communication bus.

In the Volvo EC210B LC, this fault affects the hydraulic and engine management systems' ability to share critical operational data. The CAN bus network allows various electronic control units to communicate—when PSID 99 fails, the machine may lose coordination between systems like engine control, hydraulic pump management, and instrument cluster displays. This is critical because the EC210B LC relies on seamless electronic communication for optimal fuel efficiency, hydraulic responsiveness, and emissions compliance.

Common Symptoms

When fault code 142PSID99 is active, operators may experience:

• Warning lights illuminated on the instrument panel, particularly the diagnostic or system malfunction indicator
• Intermittent loss of display data on the monitor (blank screens, missing readings for temperature, pressure, or fuel level)
• Reduced engine power or derate mode, where the ECM limits performance due to incomplete system data
• Erratic hydraulic function, including inconsistent boom or swing speed caused by disrupted communication between controller modules
• Difficulty starting or extended cranking times as the ECM attempts to verify system readiness

Potential Causes

The most common technical reasons for this code on used EC210B LC excavators include:

• Corroded or damaged CAN bus connectors, especially at the main wiring harness junction near the battery compartment or under the operator's cab
• Wiring harness chafing or breaks, particularly at flex points between the upper structure and undercarriage where constant pivoting occurs
• Faulty ECM or secondary control module (hydraulic controller, instrument cluster module) no longer transmitting valid PSID 99 data
• Loose or oxidized ground connections affecting the CAN network's voltage reference
• Water intrusion into sealed connector housings, common in machines with compromised cab seals or aged rubber grommets
• Software corruption or outdated ECM firmware requiring reprogramming

How to Troubleshoot and Fix Code 142PSID99

Step 1: Perform Visual Inspection
Examine all CAN bus wiring harnesses from the ECM to peripheral modules. On used excavators, focus on areas where harnesses pass through the swing bearing or along the boom base—these are known rub points on the EC210B LC. Check for pinched wires, exposed copper, or melted insulation.

Step 2: Test Connector Integrity
Disconnect CAN High and CAN Low connectors at the ECM and suspect modules. Use electrical contact cleaner and inspect for green corrosion or bent pins. Check connector seals for brittleness. In used machines, even minor moisture intrusion can cause intermittent communication failures.

Step 3: Measure CAN Bus Voltage
Using a digital multimeter, measure voltage between CAN High and CAN Low terminals with the key on, engine off. You should read approximately 2.5V differential (CAN High ~3.5V, CAN Low ~1.5V relative to ground). Deviations indicate a short, open circuit, or termination resistor failure.

Step 4: Check Termination Resistors
The CAN bus requires 120-ohm termination resistors at each network end. With the system powered down and harness disconnected, measure resistance between CAN High and CAN Low—it should read approximately 60 ohms (two 120-ohm resistors in parallel). Incorrect readings suggest resistor failure.

Step 5: Use Volvo VCADS Diagnostic Software
Connect Volvo VCADS (Volvo Construction Equipment Advanced Diagnostic System) or compatible J1939 diagnostic tool to the machine's diagnostic port. Monitor live CAN bus traffic to identify which PSID is dropping offline. The software can pinpoint whether PSID 99 corresponds to the instrument cluster, hydraulic ECU, or another module.

Step 6: Inspect Grounds and Power Supply
Verify all chassis ground points are clean and tight, particularly the main ECM ground near the battery. Check battery voltage (should be 12.5-14.5V with engine running) and inspect for voltage drops across corroded battery terminals.

Step 7: Replace or Reprogram Faulty Module
If diagnostics isolate a specific module transmitting PSID 99, replacement may be necessary. For used excavators, consider ECM reprogramming first—outdated firmware can cause communication protocol mismatches. Volvo dealers can flash the latest software version.

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Disclaimer: This guide provides general troubleshooting information for trained technicians. CAN bus diagnostics require specialized knowledge and equipment. Always consult Volvo service documentation and consider professional diagnostic services for complex electrical issues. Incorrect repairs can cause further damage to electronic control systems.