JLG Telescopic Crawler Boom Lift 99 Fault Code: EEPROM Fault

What does JLG Telescopic Crawler Boom Lift error code 99 mean?

Fault code 99 is an EEPROM fault on the platform or ground module controller. The EEPROM stores personalities, machine configuration digits, and calibration data such as chassis tilt sensor gain. When this memory fails or becomes corrupted, the controller may lose track of how the machine is configured or may falsely report conditions like a tilted chassis.

This code description also lists problems with the controller or a user disabling safety systems from Access Level 0, meaning the fault can surface either from a genuine hardware or memory failure, or from configuration changes made through a low access level that affect these systems.

Several distinct communicated faults fall under this code group: a platform module software update requirement, high resolution A2D interrupt or reinit failures, platform or ground module FET failures, ground or platform sensor reference voltage out of range, EEPROM failure itself, and chassis tilt sensor calibration or gain problems. Each points to a different piece of the controller's memory, power, or sensor reference system.

Common causes of 99

• Platform module software is too old to support the EIM or BPE load sensor the machine is configured to use, requiring a platform module code update.
• The ADS1213 high resolution A2D chip in the platform module stops asserting its interrupt (DRDY) line.
• The ADS1213 chip has needed to be reset 3 or more times (reinit limit).
• Platform module V(Low) FET has failed (hwfs code1).
• Ground module V(Low) FET has failed (hwfs code 1).
• The 7-volt reference voltage used for joysticks and sensors on the ground module goes out of range.
• The 7-volt reference voltage used for joysticks and sensors on the platform module goes out of range.
• A critical EEPROM failure occurs, which can reset personalities and machine configuration digits to default values.
• Chassis tilt sensor calibration information has been lost, causing the machine to indicate it is tilted at all times.
• Chassis tilt sensor gain calibration has become corrupted.

How to troubleshoot JLG Telescopic Crawler Boom Lift 99: first checks

1. 1Cycle power on the controller (EMS cycle) since this is the only listed way to reset the latched fault, then see if the fault code returns.
2. 2After a power cycle, check all machine personalities and configuration digits against the correct settings, since an EEPROM failure can silently reset these to default values.
3. 3Verify the platform module software version and confirm it supports the EIM or BPE load sensor configured on the machine, updating the code if it is too old.
4. 4Check the chassis tilt sensor calibration status. If the machine reports being tilted at all times, the calibration data programmed at the factory may need to be restored or recalibrated.
5. 5Inspect wiring and connectors feeding the joystick and sensor reference voltage circuits for corrosion, looseness, or damage if a reference voltage out of range fault is present.
6. 6Note how many times the ADS1213 chip has required reinitialization, since 3 or more resets is itself a fault condition worth documenting for a technician.

How the code clears

The action listed for this fault is: none. The fault is latched and will only reset when the controller is power cycled (an EMS cycle). There is no separate operator reset procedure, and after the power cycle, all personalities and machine configuration settings should be checked in case they reverted to default values.