KEETEC CJS4000-PRO

Powerful 4000 A jump starter with 100 W USB-C PD

The CJS4000-PRO is a professional jump starter with 4000 A peak and 800 A cranking current. Thanks to 100 W USB-C Power Delivery it recharges in about 1.2 hours and can just as quickly top up a laptop or phone. The LCD shows battery level in percent and current power in watts.

Technical parameters

Peak current: 4000 A
Cranking current: 800 A
Battery capacity: 88.8 Wh / 6000 mAh
Battery voltage: 14.8 V
Battery life: > 1000 cycles
USB-C: PD 100 W input and output
USB-A output 1: QC 3.0 · 18 W
USB-A output 2: 5 V / 2.4 A
DC output: 15 V / 10 A
Charging time: ≈ 1.2 h
Display: LCD – charge in %, power in W
LED light: yes
Dimensions: 23 × 9.8 × 5.5 cm
Weight: 1 kg
Operating temperature: -20 °C to +60 °C

Features

4000 A peak current, 800 A cranking current
100 W USB-C PD input and output – recharges in about 1.2 h
88.8 Wh battery (6000 mAh / 14.8 V) rated for over 1000 cycles
18 W QC 3.0 USB-A plus a second 5 V / 2.4 A USB-A
15 V / 10 A DC output
LCD showing charge in % and power in W
Built-in LED light
Overcharge and over-discharge protection, fuse and reverse-polarity protection

How to use

How to jump-start a 12 V vehicle

The jump starter must be charged above 20%. Don't press BOOST until the clamps are correctly connected to the vehicle battery.

01Connect the jumper cables to the unit and the clamps to the vehicle battery: red to positive (+), black to negative (−).
02Wait until the display shows READY.
03Start the engine.

What the display means

READY: The clamps are connected correctly and the unit is on. You can start the engine.
✕ + beeping: The clamps are reversed. Reconnect them to the battery correctly.
Flashing READY + beeping: The vehicle battery is flat. Hold BOOST for 2–3 seconds and, once READY is steady, start within 30 seconds.
“1” + beeping: The unit is too cold or too hot. Start once it is back between 0 and 45 °C.
“2” + beeping: Overcurrent protection. Stop cranking – the protection mode clears after 30 seconds.
“3” + beeping: More than 4 start attempts in 10 minutes. The unit enters protection mode, which clears after 10 minutes.

Downloads

CJS4000-PRO quick guide

KEETEC CJS4000-PRO

SK/CZ