How to Replace 00645038 Dishwasher Micro Pump Filter on Bosch Thermador Gaggenau — Step-by-Step

Your Bosch dishwasher stops mid-cycle and leaves standing water in the bottom. You open the door and find a puddle that won't drain. Before you call a technician, there's a good chance your micro pump filter is clogged or damaged. The 00645038 micro pump filter sits between your dishwasher's drain pump and the sump assembly, catching debris before it damages the pump motor. When this small filter fails, water backs up and your dishes stay dirty.

What You Need Before Starting

This repair works on Bosch, Thermador, and Gaggenau dishwashers including models SHX3AR55UC/06, SHE3AR56UC/06, SHX4AP02UC/53, and SHE4AM15UC/02. Gather these tools:

• Towels or shallow pan for water
• Flashlight
• Torx T20 screwdriver
• Needle-nose pliers
• Gloves (optional but recommended)

Time Required: 20-30 minutes

Difficulty: Easy

Safety First

Unplug your dishwasher or flip the dedicated circuit breaker in your electrical panel. Water will likely spill when you access the filter assembly, so lay down towels around the dishwasher base. If your dishwasher just ran a cycle, wait 15 minutes for the water to cool down. Standing water in the sump can be hot enough to burn.

Step 1: Remove the Lower Spray Arm and Filter Assembly

Pull out the lower dish rack completely. Grab the spray arm and twist it counterclockwise — it'll lift right off the mounting hub. Now you'll see the cylindrical filter assembly in the dishwasher floor. Twist this entire assembly counterclockwise about a quarter turn and lift it straight up. You'll notice water in the sump below — that's normal.

Step 2: Access the Sump Area

Use your flashlight to look into the sump opening. You'll see the micro pump filter sitting in the drain path, usually as a small cylindrical screen or mesh component. On most Bosch models, there's a retaining clip or tab holding it in place. Use your needle-nose pliers to squeeze the clip or carefully pry the old filter loose. It might be wedged in with debris and gunk — that's exactly why it needs replacing.

Step 3: Clean the Sump Housing

Before installing the new filter, wipe out the sump cavity with a damp cloth. You'll probably find food particles, glass shards, or hard water buildup. This stuff would immediately clog your new filter, so take two minutes to clean it thoroughly. Check the drain pump impeller while you're in there — spin it with your finger to make sure it rotates freely.

Step 4: Install the New 00645038 Filter

Take your new 00645038 filter out of the packaging. Notice the orientation — one end typically has a wider flange or alignment tab. Press the filter straight down into the sump cavity until you hear or feel it click into place. If your model has a retaining clip, snap it back over the filter to secure it. Give the filter a gentle tug to confirm it's seated properly.

Step 5: Reassemble and Test

Lower the main filter assembly back into the dishwasher floor and twist clockwise to lock it. Replace the spray arm by aligning the center hub and twisting clockwise. Slide the lower rack back in. Now run a rinse cycle without dishes — just let the dishwasher fill and drain to verify the new filter is working. Watch for leaks around the sump area during the first few minutes.

Testing After Installation

Start a quick wash cycle and listen for the drain pump. It should hum smoothly without grinding or rattling sounds. Open the door mid-cycle — the water should be clear without debris floating around. After the cycle completes, check that the tub is completely empty. If you still see standing water, the drain pump itself might be failing, but that's rare when the filter is the actual problem.

Frequently Asked Questions

How often should I replace the micro pump filter on my Bosch dishwasher?

Replace it every 2-3 years as preventive maintenance, or immediately if you notice drainage problems. If you wash heavily soiled dishes or don't rinse plates before loading, the filter clogs faster. Some households need replacement annually in hard water areas where mineral buildup accelerates.

Will this filter fit both Bosch and Thermador dishwashers?

Yes, part number 00645038 is the OEM component used across Bosch, Thermador, and Gaggenau dishwasher lines. It replaces older part numbers AP4339631, 00651097, and PS8730270. Check your model number against the compatibility list, but if you have a Bosch-manufactured dishwasher from the last 8-10 years, it'll fit.

Can I clean and reuse the old filter instead of replacing it?

You can try soaking it in white vinegar for an hour to dissolve mineral deposits, but the mesh often degrades or tears over time. A damaged filter lets debris through, which destroys the drain pump — a $150+ repair. At $31.99, replacing the filter is cheaper than gambling on pump damage. If your old filter shows any cracks or holes in the mesh, replacement isn't optional.