Golf cart will not move after a lithium install: what should you check first?

Direct answer: Work through a short, safe sequence before blaming the new pack: confirm the battery is awake and showing a healthy voltage and SOC, verify main power and any battery disconnect or tow/run switch, check that the charger is unplugged and any charger interlock is released, then confirm key-switch and controller enable signals and that the pack voltage matches what the controller expects. Most no-move faults after a lithium install are wiring, wake, interlock or controller setup, not a failed pack. Follow the cart maker’s service manual for pin-outs and safety.

Safety first. Park on level ground, set the brake, keep clear of moving parts, and isolate power before reseating connectors. Do not bypass BMS protection with jumper cables.

Is the battery awake? Many lithium golf packs sleep after shipping or long storage. Check the pack display or Bluetooth app if fitted. Pages for the 48V 100Ah (S51105), 48V 150Ah (S48150P) and 36V 100Ah describe BMS protection and optional Bluetooth or CAN; wake the pack per the supplier procedure, then confirm pack voltage is in the expected lithium range for a 36V or 48V cart.

Power path. Confirm the main connector is fully seated, polarity is correct, any inline fuse or breaker is closed, and a battery power switch is on. The tow/run switch on many carts is not a full battery disconnect; meters may light while the controller still has no traction enable.

Charger interlock. An installed charger plug or open interlock loop prevents drive on many carts. Unplug the charger and verify the interlock circuit with the cart manual.

Controller and gauge. Lithium voltage sits higher than lead-acid at the same SOC, which can confuse stock gauges and some controllers until they are set for lithium; see gauge wrong after lithium. Confirm the controller is programmed for the new nominal voltage and that throttle and direction inputs are present.

Wiring mistakes common on retrofits. Swapped sense leads, undersized cable, missing chassis ground for accessories, or a solenoid that never closes. Compare against the wiring diagram before replacing parts.

When to call support. If pack voltage collapses under a light load, the display shows a protection code, or the BMS will not wake, stop and contact the battery supplier with serial number, voltage readings and photos. Compatibility thinking for other power electronics is similar in spirit to checking compatibility before you buy.

Record what you find. A one-page fault log (symptoms, voltages, switch positions, codes) cuts repeat call-backs on the next cart.