1. Safety First:
* Disconnect the battery's negative terminal. This prevents accidental shorts while you're working near electrical components.
* Work in a well-ventilated area. AC systems use refrigerants, and while the amount is small, good ventilation is always advisable.
2. Locating the Drain:
The AC drain line is typically located behind the glove box or under the dashboard on the passenger side. You'll likely need to remove or partially remove the glove box to access it fully. Consult a repair manual specific to your 1997 Jeep Grand Cherokee for precise location and removal instructions. Repair manuals can be found online or at auto parts stores.
3. Identifying the Blockage:
Once you locate the drain tube (it's usually a small rubber or plastic tube), inspect it for obvious blockages. Common culprits include:
* Debris: Leaves, insects, or other debris can easily clog the line.
* Mold and mildew: Accumulated mold and mildew can restrict water flow and create a foul odor.
* Kinks or collapses: The tube itself might be kinked or collapsed, preventing proper drainage.
4. Clearing the Blockage:
* Simple Cleaning: Try using a small, flexible wire or a shop vacuum with a narrow attachment to dislodge any loose debris. A small plumbing snake might also work. Be gentle to avoid damaging the line.
* Compressed Air: Carefully blow compressed air through the drain line from the interior end (towards the exterior). Use short bursts to avoid damaging the line. Caution: Wear eye protection.
* Chemical Cleaning: If debris and mold are causing the blockage, you may try a mild solution of bleach and water (diluted carefully) and flush it through with compressed air. Thoroughly rinse afterwards. Caution: This should be a last resort, and be sure to thoroughly rinse to prevent any damage to the system.
5. Addressing Persistent Issues:
If simple cleaning doesn't resolve the issue:
* Inspect the Line's Condition: Check for kinks, cracks, or holes in the drain tube. A damaged tube will need replacement.
* Check for Evaporator Issues: In some cases, a problem with the evaporator core (inside the AC unit) might lead to excessive water buildup. This is more complex and likely requires professional attention.
* Replace the Drain Tube: If the tube is damaged or beyond repair, you'll need to replace it. This will require accessing the tube from both the interior and exterior, possibly requiring the removal of additional components. Again, a repair manual will be invaluable.
6. Reassembly:
Once the drain line is clear and any repairs are made, reassemble everything carefully, making sure the drain line is properly connected.
When to Call a Professional:
If you're uncomfortable performing any of these steps, or if the problem persists after your attempts, it's best to take your Jeep to a qualified mechanic. They have the experience and tools to diagnose and fix more complex AC system issues efficiently and safely. A persistent leak could indicate a more significant problem than a simple clog.
