Overview
GATRA’s Maintenance Department did not document any preventative maintenance services for high‑voltage batteries, high-voltage cables, battery equalizers, main disconnect switches, and automatic disconnect systems for all 39 preventative maintenance services that should have been performed on any six BEBs during the audit period. In addition, we compared the preventative maintenance checklist for the BEBs to the preventative maintenance checklist for diesel buses and found that both checklists required battery and cable maintenance (see Appendix A). However, the BEB preventative maintenance checklist did not distinguish between low-voltage or high-voltage batteries and cables and did not include all the necessary specification items. As a result, maintenance employees could have provided preventative maintenance to a low-voltage battery, which then would have appeared to be preventative maintenance to a high-voltage battery.
Without a BEB maintenance checklist that distinguishes each specific component of a BEB, GATRA cannot ensure that the high-voltage components of all its BEBs receive preventative maintenance. If GATRA does not perform these inspections, then there is potential for damage to the BEBs’ electrical components, which could result in serious injury or death to anyone in contact with the BEB and may result in avoidable damage to or loss of vehicles.
Authoritative Guidance
Chapter 2 of the GILLIG Service Manual, dated November 2021, states,
Electrical . . .
Inspect [electric vehicle] high-voltage cable condition . . . Every 24,000 miles or twice annually (whichever comes first) . . .
Jump Start Connections
Verify the boot is in place . . . Every 6,000 miles
Inspect jump start cables for routing, chafing, and loose or broken clamps . . . Every 6,000 miles
Inspect jump start housing for damage and cracks . . . Every 6,000 miles
Inspect jump start terminal ends for corrosion . . . Every 6,000 miles
Clean terminal ends and apply an anti-corrosion protectant . . . Annually . . .
High-Voltage Batteries
Visually inspect battery enclosures for signs of damage . . . Every 12,000 miles
Check for signs of coolant leaks at all connectors to battery packs . . . Every 12,000 miles
Check that [Master Safety Disconnect] handle is visually in the locked position . . . Every 12,000 miles
Inspect all [high-voltage] connections at the batter. Ensure the connector locking tab is fully locked and undamaged . . . Annually
Check for any signs of cable damage or movement from connector . . . Annually
Inspect battery mounting isolators for wear, damage or loose fasteners . . . Annually . . .
Battery Equalizer
Inspect for dirt, damage or corrosion . . . Every 6,000 miles
- If cables exhibit damage or corrosion, remove cables, repair and replace cables as required . . .
- Check torque on cables and re-torque as necessary
Main Disconnect Switch and Automatic Disconnect System
Inspect for dirt, damage or corrosion . . . Every 6,000 miles
- If cables exhibit damage or corrosion, remove cables, repair and replace cables as required . . .
Check micro-switch for function (if equipped) . . . Every 36,000 miles
Check battery switch for function . . . Every 36,000 miles
Reasons for Issue
GATRA has not established sufficient monitoring controls (i.e., policies and procedures) over its preventative maintenance process to ensure that its contracted transit provider’s maintenance employees perform preventative maintenance in accordance with the BEB manufacturer’s manual.
Recommendations
- GATRA should require its contracted transit provider to document the preventative maintenance performed on its BEBs, including maintenance on high-voltage batteries, high-voltage cables, battery equalizers, and main disconnect switch and automatic disconnect systems.
- GATRA should establish monitoring controls (i.e., policies and procedures) that include appropriate management oversight over its preventative maintenance process to ensure that its contracted transit provider performs proper preventative maintenance services on all BEBs.
Auditee’s Response
As for finding two, we are attaching the documented [preventative maintenance (PM)] service records on the BEBs, which were provided to the auditors on site at the time. While you could argue that a separate PM checklist could have been created for BEBs, there are so few things that need to be checked on the new buses that it seemed more prudent to use the existing PM checklist as electric vehicles were only a small part of our fleet at the time. With the growth of our fleet, a separate sheet has been created.
This does not change the fact that these buses are, in fact, well-maintained. With regards to monitoring controls . . . and we know that our fleet is in compliance with PM. Again, I respectfully disagree with that this should have been a finding.
Auditor’s Reply
This audit covered the time period of July 1, 2021 through June 30, 2023. The checklist GATRA refers to above was effective after the audit period, and therefore could not be considered in our audit. GATRA reports that it has taken measures to address our concerns. We will be following up on this as part of our six-month post-audit review process.
| Date published: | December 24, 2024 |
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