RV Electric Steps Won't Lock Extended - Troubleshoot Lock Switch & Control Board Issues

Short Answer

Marty, your 2008 Tiffin Allegro Bay's electric steps are retracting when the door closes because the lock-in position feature has failed. This is typically caused by a faulty step control module, a malfunctioning door switch that's overriding the lock position, or corroded wiring connections in the step system. The most common culprit in Tiffin coaches of this era is the step control module located behind the driver's side interior panel, which often develops relay contact issues after 15+ years of use.

Understanding the Problem

Your Allegro Bay's electric step system uses a control module that receives signals from multiple sources: the ignition switch, door switch, and the manual lock/unlock switch. When functioning properly, the lock position should override the door switch signal, keeping steps extended even when the door closes. Since your steps are ignoring this lock command, the door switch signal is taking priority.

In 2008 Tiffin Allegro Bays, the step system typically uses either a Kwikee or Power Gear step assembly with a dedicated control module. These modules contain relays that can develop poor contacts over time, especially in humid climates like Saskatchewan winters and summers. The lock position circuit may be failing internally, or there could be a wiring issue where the lock signal isn't reaching the module properly.

Another possibility is that the door switch itself has developed an intermittent short or is sending a continuous "door open" signal that overrides the lock position. Some owners have also found that corrosion in the step motor or control box connections can cause erratic behavior where only some functions work properly.

What You'll Need

Tools and Materials:

• Digital multimeter for testing voltage and continuity
• Basic hand tools (screwdrivers, pliers, wire strippers)
• Electrical contact cleaner and dielectric grease
• Replacement step control module (correct part for your model - verify with Kwikee or Tiffin dealer)
• Electrical tape and wire nuts if rewiring is needed

Optional but helpful:

• Service manual for your specific step system
• Replacement door switch if testing reveals it's faulty ($25-40 CAD)
• Wire brush or sandpaper for cleaning corroded connections
• Voltmeter or test light for quick voltage checks

How to Fix It

Safety Warning: Disconnect power using the battery disconnect switch or appropriate circuit breaker when making connections or repairs. Re-energize only when needed for testing. Ensure power remains disconnected while working on electrical systems. Wear safety glasses and ensure adequate ventilation when using electrical contact cleaners.

Step 1: Locate and Test the Control Module

First, find your step control module, typically mounted behind the driver's side interior panel or in the basement compartment near the steps. With the RV powered on, use your multimeter to check for 12V power at the module's input terminals. Test the lock switch by toggling it while measuring voltage at the lock position terminal - you should see voltage in the 11.5-12.8V range (battery power) or up to 13.8V (with engine running/charging system active) for proper operation when activating the lock.

Step 2: Test the Door Switch Override

With the door open and steps extended in lock position, slowly close the door while listening for any clicking from the control module. If you hear relay clicking as the door closes, the door switch signal is definitely overriding the lock position. Disconnect the door switch wire at the control module temporarily - if the steps now stay extended when locked, you've confirmed the door switch or its wiring is the problem.

Step 3: Inspect and Clean All Connections

Remove the control module and inspect all wire connections for corrosion, loose terminals, or damaged insulation. Clean any corroded connections with electrical contact cleaner and ensure all connections are tightened to manufacturer specifications. Pay special attention to the ground connection, as poor grounding can cause erratic step operation.

Step 4: Replace the Control Module

If testing confirms the module is faulty, replacement is typically straightforward. Take photos of the wire connections before removal, then transfer wires one at a time to the new module. Most Tiffin coaches use either Kwikee or Power Gear systems - check your existing module for part numbers to ensure correct replacement. Installation usually takes 30-45 minutes and requires only basic wiring skills.

Leave It to the Experts

While this repair is within the capability of most DIY RV owners, consider professional help if you're uncomfortable working with 12V electrical systems or if testing reveals complex wiring issues. Mobile RV technicians in Saskatchewan typically charge $100-150 CAD for diagnosis plus parts and labor for step system repairs.

Professional service is especially recommended if you discover problems with the step motor itself, as these units can be heavy and require specific mounting hardware. Additionally, if your coach has modified wiring from previous repairs, a technician can ensure proper system integration and prevent future problems.

Many RV service centers stock common step control modules and can often complete this repair in a single visit. Given Saskatchewan's harsh winter conditions, having the repair done properly the first time can prevent future moisture-related issues that might damage other electrical components in your Allegro Bay.