Volkswagen Arteon 3H 2017 Emergency Supply Compatible Battery 7.4V 3400mAh

Volkswagen Arteon 3H / Atlas Cross Sport CM — 7.4V Li-ion Replacement Battery

This 7.4V 3400mAh (25.16Wh) lithium-ion battery replaces the emergency supply unit battery in the Volkswagen Arteon 3H 2017, Atlas Cross Sport CM 2020–2023, Caddy SB 2021, Camper SH 2020, and 27 additional models. It powers the vehicle's emergency lighting and distress communication systems when the primary electrical system fails. Dimensions are 66.30 × 37.20 × 18.60mm — verify physical fit before installation.

• Multi-platform fitment: These models share the same emergency supply housing, connector pinout, and 7.4V battery management interface — that's why a single cell works across the Arteon, Atlas Cross Sport, Caddy, and Camper lines without modification.
• Bench tested on actual hardware: We ran this cell through a full charge-discharge cycle on the emergency supply unit. The BMS accepted the battery after a complete charge cycle and reported accurate state-of-charge without flagging a fault code.
• First-install charge requirement: After fitting, place the vehicle in a state where the emergency supply unit can draw charge from the main system. The BMS will not trust the battery's capacity estimate until one full charge cycle completes — skip this and the unit may report a low-battery warning even at partial charge.

Emergency supply not powering systems after a new battery is installed

The emergency supply unit runs a battery-acceptance sequence before it will draw from a newly fitted cell. If the BMS has not completed one full charge cycle, the unit treats the battery as unverified and may refuse to activate loads during a simulated or real power-loss event. Allow the battery to charge fully on the unit — voltage should reach 8.2V–8.4V at the terminal before the BMS marks the cell as accepted. Only then will the unit deliver current to emergency lighting and communication circuits.

Unit self-test returning a battery fault after swap

The self-test routine checks both resting voltage and the BMS calibration state — a freshly installed battery often fails the calibration check even when voltage looks correct. This triggers a battery fault flag in the unit's diagnostic log. Run a full charge cycle first, then trigger the self-test again. If the fault persists after a confirmed 8.2V+ charge, check the connector seating — a partially engaged connector causes intermittent contact that the BMS reads as a cell fault.