Results for "pcm relay"

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

Before highway driving yesterday, my gauge showed 250 PSI on the high side, but every Ford V10 manual says my 2019 Georgetown XL should max at 200 PSI. After completing full refrigerant system service including line replacement, receiver-drier, and expansion valve replacement, followed by proper evacuation and R134a charge to specification (920g), the system operates normally at idle and low RPM conditions.

However, above 2800 RPM during highway driving, the compressor cycles on and off repeatedly. System pressures appear normal during stationary testing. Is this cycling behavior a designed protective feature of the Ford V10 PCM during high load conditions, or does this indicate an underlying issue with head pressure, airflow, or refrigerant charge that requires further diagnosis? …more

Every Ford E450 I've worked on had the inertia switch behind the driver's panel — but my 2011 Freedom Elite 32r has it hidden somewhere completely different. The engine is experiencing what appears to be fuel delivery issues after a minor fender bender, and I suspect the inertia switch may have been triggered and needs to be reset.

I've already done extensive searching in the typical locations - removed both driver and passenger side kick panels completely, pulled out the glove box, and even partially disassembled sections of the dashboard. Despite checking all these common spots where Ford usually places these switches, I'm coming up empty-handed.

Could the switch be integrated into another component on this particular year and model? Are there any alternative locations specific to the E450 chassis or Freedom Elite configuration that I should be checking? I'm also wondering if some models of this year might not have a traditional standalone inertia switch at all. …more

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

Check engine light came on with a P068A code on my Ford V10 motorhome. Scanned it at AutoZone and they said ECM power relay control circuit — but the engine runs fine and I have no drivability issues. Not sure if this is something I need to fix immediately or if it can wait. …more

My 1998 Fleetwood Bounder's dashboard is sitting here completely dead with zero power reaching the ignition switch at all. The ignition switch isn't getting any power from the battery, even though I've already checked all the fuses and relays and they seem fine.

I'm still pretty new to RV electrical systems and not sure where to look next. Should I be checking somewhere between the battery and the ignition switch? I don't want to start poking around randomly and make things worse. What are the most likely culprits when you have this kind of power issue? …more

Opened up my Allegro Bay 46 ft motorhome on a Ford F53 chassis after winter storage and now it won't turn over, dashboard lights are going crazy, AND the engine makes weird clicking sounds. When I turn the key, the warning lights cycle normally (except the check engine light, which does not turn on), and the engine turns over fine when I hit the starter. However, beyond that cranking action, absolutely nothing happens - no fuel delivery, no spark.

What I really need is a systematic approach to troubleshooting this F53 no-start condition. I want to make sure I check the most likely culprits first rather than randomly replacing parts. What are the common failure points on these F53 engines that cause this exact symptom pattern where it cranks perfectly but won't fire up at all? …more

This compressor clutch for my Jayco Greyhawk E450's intermittent AC is going to cost me big — but am I even diagnosing the right part? The problem is specifically with the cooling function - the AC will blow ice cold air for about a minute or two, then the cooling suddenly stops even though the fan continues to run perfectly at all speed settings. After a few minutes, the cooling kicks back in again, then cycles off once more. This pattern repeats constantly while driving.

I've noticed that the fan motor and all the controls are working flawlessly - I can adjust from low to high speed without any issues. It's purely the cooling/compressor function that's acting up. The system isn't completely dead, which makes this even more puzzling. I suspect this might be related to the compressor clutch since the cooling cuts out so abruptly while the fan keeps running normally.

What should I be checking to diagnose this intermittent compressor clutch behavior? I want to understand the most likely causes and the proper diagnostic steps before taking it to a shop, since intermittent problems can be tricky for mechanics to reproduce and fix. …more

Opened the hood expecting to find the same starter solenoid issue that plagued my old gas motorhome — but my 2020 Fleetwood Bounder 33C with the Ford V10 keeps doing it. For the past few months, I've been dealing with this really frustrating intermittent starting problem where I turn the key and get dash lights but absolutely no cranking from the starter.

The weird thing is it's not consistent - sometimes it starts right up, other times I'll sit there for 20-30 minutes trying and then suddenly it'll fire right up like nothing was wrong. I've already replaced the ignition switch and even the starter/solenoid thinking that would fix it, but I'm still having the same issue. Battery tests good at 13.4 volts and it doesn't matter if I'm plugged into shore power or running the generator.

I'm kind of at a loss here and don't want to keep throwing parts at it. Could this be something with heat affecting an electrical component since it seems to work after sitting for a while? What should I be looking at next? …more