- 1). Park the Jetta on level ground and shut off the engine. Allow the engine to cool down. The coolant reservoir is pressurized, and opening it can cause hot coolant to spray out and possibly cause injuries.
- 2). Open the hood and locate the Jetta's coolant reservoir. The reservoir is at the rear of the engine on the driver's side.
- 3). Remove the cap of the coolant reservoir carefully. Make a note of the reservoir's maximum fill line. If there is coolant present, make sure it is compatible with the coolant to be added.
- 4). Place the narrow end of the coolant funnel into the reservoir opening. Pour the appropriate coolant into the reservoir, filling it until the coolant reaches the maximum fill line. Replace the cap securely on the reservoir.
- 5). Check the coolant level in the reservoir, making sure that the level remains constant. If the level decreases, add more coolant. If the level continues to decrease, you may have a leak in the system.
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