Pre-Disaster
During Disaster
Post-Disaster

Guide for Building Resilient E-Bus ecosystem

1. Fleet

2. Depot

3. Charging Infrastructure

4. Operating Environment

Maintenance Activities

To ensure efficient operations and improved system resilience, a two-tier, unit-replacement-based repair and maintenance system is recommended for e-bus fleets. This model reduces vehicle downtime, optimises skilled manpower and resources, and addresses the technical complexity of e-buses. Routine maintenance and quick repairs are managed at depot-level workshops, while major overhauls and specialised functions are handled at central workshops. Together, this structured approach enhances fleet availability, operational robustness, and continuity of services. Effective implementation requires targeted mitigation actions by relevant stakeholder, as outlined in the following table for enforcement and compliance.

Q1. An e-bus is brought into the depot for preventive maintenance. Before beginning inspection of the electrical system, the maintenance supervisor verifies safety precautions.

Which combination of actions is ESSENTIAL before starting any maintenance activity on an e-bus?
Q2. During a scheduled 10-day roadworthiness inspection, a technician is reviewing systems critical to safe daily operations.

Which activity is MOST appropriate under routine roadworthiness checks of e-buses?
Q3. A depot manager notices recurring battery degradation across the fleet and reviews charging practices followed by the operations team.

Which practice BEST supports battery life optimisation and thermal safety?
Q4. An e-bus reports an electrical fault related to the high-voltage battery system during operations.

What is the MOST appropriate action as per maintenance guidelines?

S.No.

Activities

Responsibility

1.

Safe Maintenance Protocol

Depot & RC, Workshop Team
OEM

2.

Scheduled Preventive and Corrective Maintenance OEM prescribed  

OEM
Depot & RC, Workshop Team

3.

Maintain Cyber Security

OEM

4.

Optimise Battery Life through proper charging protocols 

OEM

5.

Repairs and retrofitting 

OEM
Depot & RC, Workshop Team

6.

Seasonal Preventive Checks 

OEM
Depot & RC, Workshop Team

7.

Routine Roadworthiness Certification of ebuses as per periodicity laid by the STA

OEM
Depot & RC, Workshop Team
STU/ Public Transport Authority

8.

Unit Replacement – failed units replaced by serviceable or pw units (out of serviceable float of units provided by CWS)  

OEM

9.

Return Damaged Batteries 

OEM
Depot & RC, Workshop Team

All preventive maintenance activities be meticulously undertaken as per OEM prescribed schedules. These schedules are usually based on either time elapsed or kilometres operated by the bus. These tasks should be taken from the official service manuals provided by the e-bus manufacturers. Some These preventive maintenance schedules are as follows:  

  • Daily 
  • Weekly/ Fortnightly 
  • Monthly/ Quarterly 
  • Half Yearly/ Annually 

Safe Maintenance Protocol: While carrying out any repair or maintenance or inspection on an e-bus make sure that the following precautions amongst others are taken:  

  • Apply wheel chokes on all wheels 
  • Ensure ignition switch key is removed  
  • Display “Do not Start the e-bus” on steering wheel 
  • Display job card along with the tasks list at an appropriate location. 

Scheduled Preventive and Corrective Maintenance OEM-Prescribed: Additionally, some of the tasks specifically advised by the OEMs for e-buses are as here-under:  

  • Traction Cooling System: Visually inspect the radiator, visually check the radiator core and if choked (dust accumulation), clean it. Inspect the sensor wiring harness and connectors for loose connections. Visually check the coolant level and top up if low/ below the mark and check for any leakage for corrective action.  
  • Battery Cooling System (BCS): Visually inspect BCS for any coolant leaks and coolant level, and top up, if low. 
  • Electrical Connection: Visually inspect all connections of high and low voltage components for looseness. Loose terminals may lead to arcing, overheating or system faults.  
  • High Voltage Battery: Verify battery-related parameters and status through the bus dashboard by using cluster meter to ensure proper functioning of it. Additionally, inspect the battery for cleanliness, if dust or debris is observed, carryout appropriate cleaning. 
  • Electrical System: Inspect the battery mounting and check that the tightening torque range is as prescribed by the specific OEM. Inspect the LV battery posts, terminals, & rubber boots. Inspect the conditions of HV cables for its clamping and fouling.  
  • Driver Console Dashboard: Inspect and replaces switches, gauges, buzzers, light and driver controls at the driver console dashboard if found defective. Through cluster meter check or inspect for any error codes on display and rectify.  

Maintain Cyber Security: Conduct regular maintenance checks for the firewall inspection for various monitoring system and conduct regular cyber security updates.  

Optimise Battery Life through proper charging protocols: Battery packs life, generally corresponding to number of charging cycles, be optimised by following charging protocols laid by the OEMs to avoid over-charging and deep discharging. Batteries be charged by chargers with OEM specified charger rating and charging rates.  

  • Ensure that the e-bus is taken up for charging before the residual charge level falls below the OEM prescribed limit to avoid deep discharge. 
  • Charge batteries up to the max charge limit prescribed by the OEM to prevent overcharging.  
  • Charging of batteries be carried out at optimal charging rate, preferably in shade and or adequately ventilated areas, to avoid overheating and thermal runaways. After operations, allow batteries to cool down before putting them on charge. Similarly following battery charging, allow cooling time before commencing bus operations. 
  • Repair of power batteries must be carried out by certified technicians preferably at the central workshop (CWS). 
  • Repair personnel shall wear insulation gloves, shoes and they are required to use insulated repair tools. 
  • Ensure that the e-bus is taken up for charging before the residual charge level falls below the OEM prescribed limit to avoid deep discharge.
  • Charge batteries up to the max charge limit prescribed by the OEM to prevent overcharging.
  • Charging of batteries be carried out at optimal charging rate, preferably in shade and or adequately ventilated areas, to avoid overheating and thermal runaways. After operations, allow batteries to cool down before putting them on charge. Similarly following battery charging, allow cooling time before commencing bus operations.
  • Repair of power batteries must be carried out by certified technicians.
  • Repair personnel shall wear insulation gloves, shoes and they are required to use insulated repair tools.

Repairs and retrofitting at Depot Workshop (DWS):  

  • Undertake minor repairs on day-to-day basis as required. 
  • Attend to any electrical, short circuit, battery related defect as and when identified.  
  • Ensure vehicle with identified defect is kept isolated till the defect is resolved. 

Some of the other maintenance activities are discussed here-under:  

  • Seasonal Preventive Checks: Conduct preventive checks before on-set of summer/ rainy seasons and replace any vulnerable parts in advance. 
  • Routine Roadworthiness Certification of e-buses as per periodicity laid by the STA: Carryout routine in sections to ensure vehicle roadworthiness and system readiness in accordance with OEM defined task and periodicities (daily/ 10-Day/ monthly):  
  • Verify vehicle starting condition, fault code, voltage etc 
  • Visually check for coolant levels of the battery cooling system and top up, if low. 
  • Inspect brake system, including checks for air leakages with brake pedal in both engaged and disengaged position. 
  • Check charging interfaces, including charger flaps doors, connectors and related components for proper functioning. 
  • Review dashboard alerts and error messages and initiate corrective actions as necessary. 
  • Inspect electrical system, including BMS connections, electric motor connections, wiring harness panels, and ensure proper locking, sealing, and fitment of rubber gaskets.  
  • Verify proper functioning of electrical fitments and accessories, including lighting systems (front and rear), LV batteries (clean terminals, check electrolyte levels where applicable), and other auxiliary systems. 
  • Confirm functionality of Intelligent Transport Systems (ITS), Destination Display boards, CCTV cameras, communications systems, etc and address any identified deficiencies. 
  • Ensure proper operation of passenger and emergency doors, confirming opening and closing within the prescribed time (e.g., within 4 seconds) and other safety features. 
  • Attend to driver-reported complaints promptly to prevent escalation of faults. 
  • Continuously update preventive maintenance schedules and tasks based on operational data, fault trends, and data-driven analysis to improve reliability, safety, and overall performance. 
  • After operations provide cooling time before taking up any repair or maintenance activities on e-buses. 
  • Carryout all repairs, retrofitment or removal of batteries and components etc, only with the help of trained and qualifies technicians.  

Return Damaged Batteries: Any damaged batteries are to be promptly returned to the OEM for inspection and safe handling.

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