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ECM Low Battery Warning RV: Complete Diagnosis & Fix Guide
Electrical Medium 2-6 hours 230 👍 1

ECM Low Battery Warning RV: Complete Diagnosis & Fix Guide

During a family trip, my 2005 Fleetwood Discovery 39S threw code 168-1 for low ECM battery voltage and went into full shutdown mode—is this dangerous with kids onboard? Engine cut out, transmission selector went dark, ABS warnings everywhere - the whole nine yards. Scared the heck out of me when it happened on the interstate!

I'm seeing this seems to be a thing with these diesel pushers, but I'm drowning in conflicting info online. Some say it's the chassis battery, others blame alternator issues, and I've even seen posts about ECM power supply problems on the Caterpillar engines. What's the actual step-by-step process to track this down? And more importantly, how do I fix it so it doesn't leave me stranded again? Really need a complete walkthrough of what causes this code and the proper repair approach. …more
Ford F53 7.5L RV Won't Start: Fuel Pump Relay Voltage Drop Fix
Engine Hard 4-6 hours 171 👍

Ford F53 7.5L RV Won't Start: Fuel Pump Relay Voltage Drop Fix

Woke up to my 1996 Ford F53 7.5L motorhome eating through my patience and wallet with this no-start issue that keeps coming back. It cranks strong but absolutely will not start, and I've been chasing this problem for weeks now. The engine ran fine for about 3-4 minutes one day, then just died and hasn't started since.

I've already done quite a bit of diagnostic work:
- Replaced PCM and distributor
- Fuel pump works when powered directly
- Battery is fully charged
- Checked fuses and relays
- PCM relay voltage drops from 12.2V to 9.3V with key on
- Fuel pump relay only shows 3.3V at pin 86 (should be 12V)
- Inertia switch tested at 1.7V at connector
- ANL 178 fusible link fluctuates between 0.3-0.6V

The engine will only start with starter fluid when the SPOUT is removed. I'm getting only 5.5V at the fuel pump connector.

Has anyone dealt with this specific issue on an F53 chassis? I really need to get this RV back on the road and I'm running out of ideas! …more
Monaco Diplomat Rear Air Suspension Won't Dump Fully - Troubleshooting Guide
Plumbing Medium 1-2 hours 169 👍

Monaco Diplomat Rear Air Suspension Won't Dump Fully - Troubleshooting Guide

Last week my 2006 Monaco Diplomat's rear air bags started refusing to dump all the way down when I hit the air dump before leveling. The front dumps fine, but the back stays partially inflated.

I'm still pretty new to RV maintenance and not sure where to start troubleshooting this. Should I be hearing air escaping when I activate the dump? What are the most common causes when rear air bags won't dump completely? Any guidance on what to check would be really appreciated! …more
No 12 Volt Power in RV: Complete Troubleshooting Guide
Electrical Medium 30-90 min 140 👍

No 12 Volt Power in RV: Complete Troubleshooting Guide

Turned the key and nothing works on 12 volt — no lights, no water pump, no slides. Batteries show 12.6 volts on the multimeter so they're fully charged. House batteries seem fine but zero power is getting to any of the 12V circuits inside the coach. …more
How to Protect Your RV Alternator When Charging Lithium Batteries: DC-
Electrical Medium 2-4 hours 105 👍

How to Protect Your RV Alternator When Charging Lithium Batteries: DC-

Tried everything my neighbor did to charge his LiFePO4 batteries but mine keeps frying the alternator while his works flawlessly — what's different? I want to install a temperature sensing device that can interrupt charging by opening the solenoid between chassis and house charging systems if the alternator gets too hot. I'm looking to spec out components and understand the installation process, and I'm open to hearing why this might not be a good approach. My goal is preventing alternator overheating when these lithium batteries draw high current compared to my old flooded or AGM batteries. I'm looking for technical feedback and am totally open to critique. …more
RV Electric Leveling Jacks Won't Extend - Fix Clicking Issue
Slideouts Medium 45 minutes 99 👍

RV Electric Leveling Jacks Won't Extend - Fix Clicking Issue

Wondering if I should drop $800 on new electric leveling jacks or if this annoying clicking issue can actually be fixed first? The jacks were working perfectly fine on our last camping trip about two weeks ago, but now when I try to extend them, I can hear a distinct clicking sound coming from the controller panel, yet none of the jacks actually move or extend. The clicking happens consistently when I press the extend button, so it seems like the system is trying to respond, but something is preventing the actual mechanical operation.

I'm wondering what the most common causes are for this specific symptom - where you get the clicking from the controller but no actual jack movement. I'd like to understand the logical troubleshooting sequence, starting with the easiest things to check first before I dive into more complex diagnostics. The RV has been sitting plugged into shore power, but I know these systems can have multiple potential failure points including electrical, hydraulic, or control issues.

What should I be checking first, and what's the typical progression for diagnosing electric leveling jack problems that manifest with clicking sounds but no extension? …more

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How to Fix RV Transfer Switch Not Detecting External Generator - Complete Troubleshooting Guide
Engine Hard 4-8 hours 98 👍

How to Fix RV Transfer Switch Not Detecting External Generator - Complete Troubleshooting Guide

The automatic transfer switch on my 1999 American Eagle detects shore power and onboard diesel genset fine, but won't recognize my external portable generator — can I fix this for under $50? The generator runs fine and produces power, but the transfer switch doesn't trigger to use it.

What causes this issue and what are my options to get the ATS to work with an external generator? …more
RV Emergency Start Switch Not Working: Complete Troubleshooting & Repair Guide
Electrical Medium 30-60 minutes 97 👍

RV Emergency Start Switch Not Working: Complete Troubleshooting & Repair Guide

Every time the temperature hits 85°F or higher, my RV's emergency start switch completely fails — works perfectly in cooler weather, but now my chassis battery is dead while house batteries stay charged. When I press the emergency start button, absolutely nothing happens - no sounds, no response at all.

I'm worried there might be something wrong with the system or that I'm not using it correctly. Should I be hearing some kind of click or sound when I press the button? Could there be blown fuses I need to check? I'm hesitant to keep trying without knowing if I might cause damage to the electrical system. What's the proper troubleshooting process to safely figure out why this emergency start feature isn't connecting my house batteries to help start the engine? …more
Ford F53 No Spark: Complete Ignition Troubleshooting Guide
Engine Medium 2-4 hours 96 👍

Ford F53 No Spark: Complete Ignition Troubleshooting Guide

Halfway through a cross-country trip, my Ford F53 Class A motorhome with the 7.5L V8 cranks but won't fire, has zero spark, AND left me completely stranded. The issue began intermittently with starting problems, then progressed to a complete no-start condition with zero spark at both the coil and distributor.

I've systematically replaced the distributor, ignition control module (ICM), and coil, but the no-spark condition persists. This is an EFI system without a crank position sensor - my research indicates it relies on the pickup coil within the distributor for ignition timing.

What are the most likely causes for this complete ignition failure, and what diagnostic steps should I follow to isolate the root cause? I need a methodical troubleshooting approach since parts replacement hasn't resolved the issue. …more
HWH 625S Slide Out Not Working: Step-by-Step Control Box Bypass & Repair Guide
Slideouts Medium 2-3 hours 94 👍

HWH 625S Slide Out Not Working: Step-by-Step Control Box Bypass & Repair Guide

Wondering why my 2008 Winnebago Adventurer 38J's HWH 625S slide out won't budge after replacing the solenoid, cleaning connections, and checking fluid levels? The passenger slide won't extend or retract from the wall switch, but when I manually operate the solenoid valves, the slide moves perfectly in both directions.

I've already replaced the solenoid valves, so I know they're good. The problem seems to be that power isn't reaching the solenoids from the switch - everything routes through the control box first.

Can I safely bypass the HWH control box by connecting the switch wires directly to the solenoid wires? What should I check before attempting this bypass? …more
Dead House Batteries on 50 Amp Shore Power: Troubleshooting Guide
Electrical Medium 30-60 min 92 👍

Dead House Batteries on 50 Amp Shore Power: Troubleshooting Guide

Turned on my 2024 Entegra Reatta XL this morning to find the house batteries completely dead again despite being plugged into 50 amp shore power—third time this season and I'm done guessing. New batteries, good connections, power was working fine for days then died completely. Voltmeter shows 12.69V on chassis, 4.7V on house batteries at the BIM.

What's the proper troubleshooting sequence for house batteries not charging on shore power? Need to check converter, breakers, and connections but want to do this systematically. …more
How to Fix RV Rear Brake Lights and Hazards Not Working - Common Grounds & Connections
Electrical Medium 1-2 hours 92 👍

How to Fix RV Rear Brake Lights and Hazards Not Working - Common Grounds & Connections

Spent months planning our cross-country trip leaving next week and my RV's rear brake lights and hazards just completely stopped working. My 1998 National Tropical (on a '97 Ford F53 chassis with the trusty 460 V8) has decided to get creative with its lighting situation. The rear brake lights and 4-way hazards have completely given up the ghost - nothing, nada, zero response from the back end. But plot twist: the turn signals work just fine back there, and everything up front (brake lights, hazards, turns) is working perfectly.

I'm scratching my head because if it was a fuse issue, wouldn't ALL the lights be affected? The fact that some work and others don't has me thinking it's something more specific. Any ideas where I should start poking around to solve this electrical mystery? …more
RV Whirlpool Refrigerator Cycling Every 30 Minutes: Is It Normal? [202
Ac Refrigeration Easy 30 minutes 92 👍

RV Whirlpool Refrigerator Cycling Every 30 Minutes: Is It Normal? [202

Looked everywhere for answers on my Whirlpool residential refrigerator cycling every 30 minutes—my neighbor says it's normal, RV dealer says it's broken, YouTube says something else entirely. The ambient temperature here is around 65°F, and I have both the fridge and freezer set to the 3rd snowflake setting.

I haven't timed it exactly with a stopwatch, but I keep noticing it kicking on again after what feels like a short time. I'm concerned this frequent cycling might be a sign of a problem or could lead to premature failure. I try to keep the vents clean when I can access them. Should I be worried about this 30-minute cycle pattern, or is this within normal range for an RV refrigerator in these conditions? …more

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Complete Newmar RV Lithium Battery Upgrade: DC-DC Charger and BIM Wiring Guide
Solar Batteries Hard 6-8 hours 91 👍

Complete Newmar RV Lithium Battery Upgrade: DC-DC Charger and BIM Wiring Guide

Staring at my 2019 Newmar's freshly wired lithium upgrade with Victron BVM-712, Orion XS DC-DC charger, and Cerbo GX — finished yesterday but the system still isn't charging properly.

The main issue is I can't figure out how to properly integrate my existing boost switch with the new DC-DC charger setup while maintaining the ability to trickle charge chassis batteries. Currently, my Orion XS DC-DC charger flows only one way from engine alternator to lithium batteries. Should I replace the existing BIM with a LI-BIM, which would be in series with the 2/0 cable? Is there a control wire on the Orion XS that will allow flow from lithium to chassis batteries while on shore/inverter power?

I'm considering adding a 120V battery tender for chassis batteries, but want to confirm what modifications might be needed to my existing BIM. Can someone provide guidance on the correct wiring approach? …more
Onan 7000 Generator Low Voltage to Fuel Pump: Complete Repair Guide
Engine Medium 2-3 hours 89 👍

Onan 7000 Generator Low Voltage to Fuel Pump: Complete Repair Guide

Our Onan 7000 Marquis generator is hitting us with low voltage to the fuel pump for the third time this season and I'm done with guessing games. When I check the voltage at the fuel pump, I'm only getting 9V instead of 12V, and surprise surprise - it won't start. But here's the kicker - if I jump 12V directly to the pump, the thing fires right up and runs like a champ.

Obviously there's a voltage drop happening somewhere between the control board and the fuel pump, but I'm not sure where to start looking. Could be corroded connections, maybe the control board itself is going bad, or some wiring issue in the fuel pump circuit? Anyone dealt with this before and know the most common culprits? …more
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