Dishwasher Repair Guide

Main Points to Remember

The control panels on modern dishwashers can be daunting, with numerous buttons, dials, and features that make the appliance seem too complex to repair. However, that’s not true. Aside from the control panel, dishwashers have remained largely unchanged in their basic structure for the past twenty years. Many dishwasher problems can be solved on your own, and this article will provide practical tips for DIY repairs and maintenance.

Dishwasher components can often be replaced as a complete unit, which is typically more affordable and simpler than calling in a professional technician for repairs. If you're uncertain whether a part is still functional, remove it and take it to a professional for evaluation. Based on their repair estimate, you can then decide whether to replace the part or repair the old one.

Dishwashers typically operate on either 115-volt or 120-volt electrical power. The water used comes directly from your water heater, and wastewater is drained through the kitchen sink’s drainpipe. Dishwashers are not linked to the cold-water supply. For optimal cleaning results, adjust your water heater’s temperature to at least 140°F. Water temperatures lower than this might not clean dishes effectively, unless your dishwasher is a newer model that heats incoming water. The water shutoff valve for the dishwasher is generally located beneath the adjacent sink.

Warning: Since dishwashers are connected to both plumbing and electrical systems, it's important to consider both before working on the appliance. Always ensure the dishwasher is unplugged or the power is turned off before starting any repairs. Additionally, remove the fuse or trip the circuit breaker controlling the unit, either at the main panel or a separate one. Also, shut off the water supply to the dishwasher from the valve typically located in the basement or crawl space beneath the kitchen.

Essential Dishwasher Maintenance Checks

If your dishwasher isn't working, here are a few checks you can make to troubleshoot the issue:

Step 1: Verify that the dishwasher is getting power. If it's plugged into a wall outlet, inspect the cord, plug, and outlet to ensure they are working correctly. Also, confirm that the switch controlling the outlet is turned on. For built-in dishwashers, check the main electrical panel for a blown fuse or a tripped circuit breaker and restore the circuit. In older homes, the dishwasher might be connected to a separate panel—check for a blown fuse or breaker there and restore power.

Step 2: If the power is on, but the dishwasher still isn't working, the outlet switch may be faulty. To test it, use a voltage tester. Remove the switch cover plate, place one probe on each terminal, and see if the tester light comes on. If the bulb lights, the switch is working; if not, replace the faulty switch with a new one of the same type.

Step 3: Ensure the door is securely closed and latched. The dishwasher will not start unless the latch is fully engaged. To test the latch, close and latch the door, pressing the latch firmly. While holding it closed, turn the control knob to the ON position. If the dishwasher runs, the latch may be faulty and needs cleaning, tightening, or replacing.

Step 4: Check that the water supply is on and that the water temperature is sufficient. A problem with the water heater could prevent water from reaching the dishwasher. Test the hot water from a sink or bathroom faucet. If hot water flows, the issue likely isn't with the water heater.

Step 5: Double-check that the control panel settings are correct. Newer push-button controls can be very sensitive, so ensure the buttons are pressed down securely.

If you've completed all five checks and still haven't found the issue, it's time to investigate further into the dishwasher itself.

Disassembling the Dishwasher

Most dishwashers allow access to their internal components through the front door. You can make several repairs by simply opening the door and reaching in to fix parts like the sprayers, strainers, float switch, racks, and door latch.

To reach the control panel on the door, remove the screws around the panel. These screws may be hidden beneath molding strips, which typically snap onto the metal housing. Use a stiff-bladed putty knife or screwdriver to pry off the strips or remove a small setscrew that holds the molding in place. The control knobs are either friction-fit on shafts or secured with tiny setscrews at the base. In some models, you may need to remove the entire front door panel to access the control components. This panel is fastened with screws around the inner edges of the door.

On many models, after removing the control panel, you can take off the door panel by unscrewing the fasteners that hold it in place. These screws may be hidden behind trim moldings, which can be pried or slipped off. To access the motor, pump, hoses, inlet valves, and other internal components, remove the lower access panel. This can typically be done without removing the entire door. The panel may be secured with screws, or it may simply lift off metal hangers.

If your dishwasher is portable, tilt the machine onto its back or side before removing the control door or lower access panels. This position may provide a more convenient angle for working.

Once you're inside the dishwasher, familiarizing yourself with the main components and their functions will help you identify the issue. In the next section, we'll go over the primary parts and how to check them.

Repairs for the Door and Switches

When your dishwasher isn't functioning correctly, it's important to check several key components, including the door gasket, door latch, switches, and timer.

Replacing the Door Gasket

If you notice water leaking through the door of the dishwasher, the gasket is likely the culprit. Open the door and inspect the gasket. It should be flexible and in good condition. If it's brittle, cracked, or hardened, it's time for a replacement.

After installing the new gasket, verify that it fits snugly against the door frame. There should be no gaps or bulges between the gasket and the frame. If needed, adjust the retaining screws or reposition the gasket in its clips or the door channel. Then run the dishwasher through a cycle and check for any leaks.

If you find a leak and the gasket seems properly positioned, try adjusting the door latch. The goal is to ensure the gasket presses against the door frame without being squashed flat when the door is latched. Make adjustments to the latch or gasket as necessary to achieve a secure fit against the door frame.

Servicing the Door Latch

The latch on a dishwasher door is subjected to frequent opening and closing, which can cause mechanical issues over time. The latch might become loose, or it could slip out of place, disrupting the alignment and preventing the door from closing properly. If this happens, the latch will fail to engage, and the dishwasher will not start.

In many situations, you can resolve the issue by adjusting the position of the latch. Loosen the screws securing it, then gently shift the latch using your fingers or pliers, as the screw slots are designed for this adjustment. Close and open the door to check if the latch is properly aligned. Tighten the screws to secure it in the correct position.

After repositioning the latch, test it to ensure it's functioning correctly. Close the door, latch it, and turn the control knob to the ON position. If the dishwasher still doesn't start, the latch is likely defective. Replace it with a new one, connecting it the same way the old one was installed. You may need to move the new latch back and forth a few times before it operates properly.

Servicing the Door Switch

On many dishwashers, the latch activates a switch that controls the timer and other components. If the latch isn't fully engaged or if the switch is malfunctioning, the dishwasher won't run. Here’s how to test and repair the door switch:

Step 1: Close the door and hold the latch firmly in place. This step is especially effective on units with a lever-style latch. Then, set the control to the ON position. If the dishwasher operates, the issue is likely a misaligned latch. Use a screwdriver to adjust the lock unit. If the machine still doesn't work, the switch may be faulty.

Step 2: Test the switch using a volt-ohm-milliammeter (VOM) set to the RX1 scale. Remove the door switch cover panel and disconnect one of the electrical lead wires from the switch terminals. Attach one probe of the VOM to each terminal and close the dishwasher door. If the meter shows zero, the switch is functioning. If the reading is above zero, the switch is defective and should be replaced.

Step 3: Replace the faulty switch with a new one of the same type. Reconnect the new switch in the same manner as the old one.

Servicing the Float Switch

Dishwashers typically use a float switch to prevent overfilling. This switch is positioned at the bottom of the appliance. Here's how you can check and replace it:

Step 1: Open the door and remove the bottom dish rack. Inspect the float valve to see if it's stuck. If so, clear away any food particles around it. Gently tap the top of the float with the handle of a screwdriver to loosen it.

Step 2: If tapping doesn't resolve the issue, take off the lower access panel and locate the bottom section of the float and float switch. Test the float switch with a VOM set to the RX1 scale. Detach one electrical lead from the switch terminal and attach one probe of the VOM to each terminal. If the meter shows zero, the switch is not faulty. The issue might be with the timer. If the meter reads above zero, the switch is defective.

Step 3: Replace the faulty switch with a new one designed for your dishwasher. The switch is secured to a mounting bracket with screws; remove these screws to take out the old switch.

Step 4: Install the new switch by connecting it the same way as the old one was connected.

Servicing the Timer and Control Switches

Since the timer regulates numerous operations, a malfunctioning timer can lead to various issues. The timer is a complex part, so it’s recommended not to try fixing it yourself. To test the timer, use a VOM set to the RX1 scale. First, remove the front control panel to access the timer, which is located right behind the main timer control knob. Disconnect one of the wires from the timer's terminal, and attach one probe of the VOM to each terminal. If the meter reads zero, the timer is functioning correctly. If it reads higher than zero, the timer is defective and needs replacing.

If possible, follow the same procedure to test the selector and cycle switches. However, the wiring for these switches may be too intricate to easily understand. If you’re unsure about handling these switches, it's best to call a professional. Replace any faulty timer or control switch with a new one designed for your dishwasher.

The timer connects to several wires that provide power to operate the dishwasher’s various functions. To replace the timer, have someone assist you by holding the new timer next to the old one. Connect the wires to the new timer one at a time, removing the old wire and attaching the new one to ensure proper connections. The wires may be friction-fit on the terminals, in which case, use long-nosed pliers to remove them. Avoid pulling on the wires directly to prevent breaking the connection.

Once the wires are connected, position the new timer, secure it as the old one was, and reinstall the control panel and knobs.

If your dishwasher isn’t filling with water as it should or isn’t drying the dishes properly, it’s likely a problem with the valve or heating element. In the next section, we’ll go over how to diagnose these issues.

Valve, Dispenser, and Dish Rack Repairs

Regular maintenance of the various valves, detergent dispenser, and dish rack can ensure that the correct amount of water and detergent are effectively working in your dishwasher.

Servicing the Water Inlet Valve

The water inlet valve is responsible for regulating the amount of water entering the dishwasher. It can be triggered by the timer or a solenoid. If your dishwasher isn’t filling with water, the issue may lie with this valve.

Step 1: Ensure that the water supply to the dishwasher is on and check the water heater for any issues. A shutdown of the water heater could lead to a disruption in the water supply to the dishwasher.

Step 2: Verify that the timer is functioning and completing its programmed cycles. If both the water supply and the timer are working correctly, the issue is likely with the inlet valve.

Step 3: Inspect the inlet valve, which is located beneath the dishwasher’s tub. A malfunction may occur if the screen inside the valve becomes blocked with mineral deposits. To resolve this, remove the screen using a screwdriver, rinse it thoroughly under running water, and then replace it.

Step 4: If the valve is operated by a solenoid, it is typically attached to the side of the dishwasher. Lightly tap both the solenoid and the valve with the handle of a screwdriver to dislodge any obstruction. Then restart the dishwasher.

Step 5: If the dishwasher still isn’t filling, test the solenoid using a volt-ohm-milliammeter (VOM) set to the RX1 scale. Disconnect one electrical lead from the solenoid, then connect the VOM probes to the solenoid’s terminals. A reading between 100 and 1,000 ohms indicates the solenoid is functioning. If the reading exceeds 1,000 ohms, the solenoid is faulty and needs replacing.

Step 6: If required, replace the solenoid with a new one that matches the size and type of the original. Connect the new solenoid in the same manner as the old one was connected.

Severely worn or deformed inlet valves cannot be repaired. If the valve is damaged, replace it with a new one designed for your dishwasher. The valve is typically secured to a mounting bracket with screws. Disconnect the valve from the water supply, remove the screws, and take out the old valve. To install the new valve, reverse the disconnection and installation steps.

Servicing Drain Valves

Servicing Drain Valves

Certain dishwashers are equipped with drain valves, which are used only in models with non-reversible motors. If the drain valve fails, it's best to consult a professional technician for assistance.

Servicing the Heating Element

The heating element helps to dry the dishes. In many dishwashers, it is located around the screen at the bottom of the tub housing and resembles an electric oven element. Although it is rare for the heating element to fail, it can burn out. If you suspect the element is faulty, follow these steps:

Step 1: Test the element with a volt-ohm-milliammeter (VOM) set to the RX1 scale. Start by removing the bottom access panel of the dishwasher and disconnect one of the power leads to the element. Attach one probe of the VOM to each terminal of the element. A reading between 15 and 30 ohms means the element is functioning correctly. If the reading is higher than 30 ohms, the element is defective and needs to be replaced.

Step 2: If replacement is necessary, take out the faulty heating element and replace it with a new one designed for the dishwasher. Disconnect the electrical leads from the terminal screws and remove any fasteners holding the element in place. From inside the tub, carefully lift the element out. It may be held by clips and ceramic blocks, but you can easily thread it past these spacers. Place the new element in position, reconnect the power leads, and secure it with the fasteners.

Servicing the Detergent Dispenser

Leftover detergent from previous wash cycles can create issues with the soap dispenser. This residue can obstruct the dispenser and interfere with the spring mechanism that activates the flip-out tray, or it can cause the tray's pivot action to slow down. If the dispenser is not opening, make sure that dishes, pots, or pans aren't obstructing the dispenser and that the dish racks aren't blocking it. Also, check for cracks in the dispenser tray. If the detergent left in the tray is more liquid than damp, the tray may be broken.

If you're unable to easily fix the problem, consider replacing the entire dispenser unit. This is generally simpler than trying to disassemble and replace individual components. Use a new dispenser made for your specific dishwasher model. The screws securing the dispenser may be on the front of the unit, or you might need to remove the front door panel to access them. Once the old dispenser is removed, install the new one, connecting it in the same way as the previous unit.Troubleshooting Dish Racks

Dish rack issues typically arise when the racks are forced back into the tub housing after being fully loaded. Rough handling can put enough pressure on the roller wheels to break them or knock the racks off their tracks. The solution is simple: avoid forcing the racks into place.

The repair is equally straightforward. Begin by removing the racks, either by pulling out the small metal pins holding them in place or simply lifting the racks out of the tracks. Once removed, reinstall the racks so they roll smoothly. If the rollers are damaged, replace them with new ones of the same type. The rollers may be secured by friction to their hubs; you can pull them off for replacement. If they're attached with spring clips, use pliers or a screwdriver to remove them. If you can't replace the rollers individually, consider replacing the entire rack.

A noisy wash cycle or water that refuses to drain are issues that can often be resolved on your own. In the next section, we'll guide you through how to identify and fix these water-related problems.

Motor and Water-Related Repairs

Maintaining the cleanliness of the sprayer arms, strainers, and water pump in your dishwasher can help prevent issues before they arise. Here's how to check on these vital components.

Cleaning the Sprayer Arms

Sprayer arms typically don’t present any issues, but occasionally, the spray holes may become clogged with detergent or mineral deposits. In such cases, cleaning the holes is necessary to restore proper function. Start by removing the lower sprayer arm by unscrewing the cap that secures it to the motor shaft. Clean it thoroughly with water and mild dish soap. Sharpen a pencil, break off the lead, and use the pointed end to clear the holes. Alternatively, a wooden manicure stick can be used to clear the holes.

Avoid using toothpicks, matches, or metal objects for this task. Wooden sticks that are too light may break off inside the ports, causing blockages, while metal can damage and widen the ports. Once the cleaning is done, reattach the sprayer arm to the motor shaft and twist the cap to secure it. Repeat the same cleaning process for the upper sprayer arm.

Removing and Cleaning the Strainer

The strainer sits directly beneath the lower sprayer arm. If it becomes clogged with food particles and detergent, it can cause the dishwasher to flood or overfill. Some dishwashers have a strainer made of two semicircular halves, either plastic or metal. To remove this type, simply pry it up. In other models, the strainer is a single piece. For these, remove the cap that holds the sprayer arm in place, then remove both the arm and the strainer.

Clean the strainer in your kitchen sink using warm water and a mild household detergent. Use a stiff brush to scrub away any debris from the holes and slots. Rinse thoroughly and return the strainer to its original position. If your strainer has a removable part for regular cleaning, check it and clean it after every dishwashing cycle.

Troubleshooting Leaks

If your dishwasher is leaking and you've ruled out issues like tub overfilling, pump failure, or inlet valve malfunctions, the leak may be due to faulty plumbing connections. Dishwashers typically connect to the water supply through metal pipe fittings, and leaks could occur at these points. If the fittings are threaded, tighten them using an adjustable wrench. If tightening doesn't fix the issue, the threads may be stripped or the fitting could be cracked or damaged. In such cases, replacing the fitting is necessary.

Dishwashers usually expel used water through a pipe or hose that connects to the drain or garbage disposer under the kitchen sink. Flexible hoses may crack over time due to repeated exposure to hot water. Inspect the hose for any damage, and replace it if necessary. If the hose is leaking at the connection points with the disposer or dishwasher, try tightening the fittings or clamps, or replace the clamps altogether. Be sure to also check for leaks around the inlet valves, drain valves, and any flexible hoses or hose connections. Tightening or replacing clamps can fix leaks at these points, and damaged hoses should be replaced.

Servicing the Water Pump

In most dishwashers, the water pump is situated beneath the lower sprayer arm. This essential component circulates water throughout the dishwasher. The pump includes two impellers, one on top and one on the bottom. These, along with other parts, can get clogged with food or detergent. Here's how to take apart the pump for maintenance:

Step 1: Start by removing the cap that secures the sprayer arm in place.

Step 2: Take off the sprayer arm, the screen, the pump housing, a bolt, the upper impeller, the food disposer blade, a spacer plate, the impeller hood, a flat plate, an O-ring, and the lower impeller. Organize the parts in the order they come off so you can easily reassemble them later.

Step 3: Wash each part carefully using a mild detergent solution. Replace any components that show signs of wear with new, dishwasher-compatible parts.

Step 4: Install fresh seals, such as the O-ring or other washers, to ensure a tight fit.

Step 5: Put the pump back together, making sure to follow the order of the parts as you reassemble them.

To access the water pump, you need to first remove the sprayer arm and screen, followed by the pump housing. Unscrew the bolt, and the pump components will be ready to disassemble.

On certain dishwashers, the lower impeller acts as a drain pump. These models typically have a reversible motor, while non-reversible motors rely on drain valves, as explained earlier. If your dishwasher has this impeller pump system and the water won't drain, try cleaning the lower pump impeller. This might resolve the issue. If not, it’s best to call a professional for assistance.

Motor Repairs

If your dishwasher motor is malfunctioning, avoid attempting to repair it yourself. It’s recommended to call a professional technician to either repair or replace the motor. However, before contacting service, ensure the timer is functioning correctly and the dishwasher is properly powered.

Don’t let water leaks, noisy cycles, soap residue, or other issues keep you from using your dishwasher. Most common problems can be easily fixed by following the guidelines provided in this article.

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