June 29, 2016
Filed under RV Tech Q&A
I have a strange problem with my 2010 Fleetwood Bounder 35E on a Ford chassis with a Triton V-10. After the motorhome has been parked for a few days (in a park with hookups), with the key out of the ignition, I will hear a random beep and the message check gauges where the odometer reading is located. I looked this up and it says it is either low fuel, low oil pressure or low battery. None of these should be a concern with the engine off. I called Ford’s owner helpline and they told me to run the engine for 30 minutes. I did that and still got the message and beep. How can I determine the cause of this, and how can I fix it? It does not always happen, but once it starts happening, it won’t quit for a while. I can pull a fuse to make it stop, but that seems like we are treating the symptom and not the real problem.
Dave Krajcar | Vancouver, Washington
Where you mention that low fuel, low oil pressure or low battery should not be a concern with the engine off, the last item is of concern. The engine-starting battery on most coaches does not get charged by the power converter when plugged in to 120-volt AC or the genset is running. On these models it only gets charged when the engine is running, from the alternator. However, even when everything seems to be switched off, there are various small parasitic current draws (from electronic memories, etc.) from that battery that are leading to the discharge problem you refer to. Another possibility is that after about six years, if you have the original battery, it is starting to deteriorate; this should be tested.
To determine if your electrical system charges the engine battery, simply measure voltage at that battery’s posts with a multimeter. It should read about 12.6 volts. Then plug in the shorepower cord and measure battery voltage. If the voltage comes up noticeably, it is getting charged; if not, well you know the answer.
I assume when you say you can pull a fuse to make it stop, you are referring to the fuse for the dash indication. No, you don’t want to do that, but pulling one or more fuses may actually be what’s needed to stop the current draw. However, there’s a better way. ISL Products (http://www.lslproducts.net) makes kits (Trik-L-Start and Amp-L-Start) that will transfer power that comes from the power converter to the coach batteries on to the engine-starting battery and disconnects it when power is not flowing.
Workhorse Intermittent Limp Home Mode
My motorhome is a 1999 38-foot Newmar Mountain Aire on a Workhorse chassis with a GM 454 cid engine and Allison four-speed transmission. My wife and I have owned the coach for three years and have driven it back and forth across the country without a problem. A few months ago I went to pull out for a short overnight trip and the coach started to accelerate then went into limp mode with no power. I turned the engine off and looked for blown fuses. When I restarted the coach the error code (reduced engine power mode, engine check light) had cleared and upon starting back up the problem seemed to have cleared itself. The rest of the trip went without a hitch. As with most problems that just disappear, this one came back over the next few months and progressively got worse such that I would be driving down the highway and suddenly go into limp mode. My mechanic ran a scan and got a P1125 error indicating fuel air mixture issues. Pretty vague, and to his credit he suggested I take the coach to the local Chevy dealer to see if they could narrow it down some. The Chevy service manager said they didn’t work on motorhomes but agreed to run his handheld scanner to check for error codes. His scan turned up the same error code P1125; however, instead of showing a fuel air mixture problem it indicated an Accelerator Pedal Position Sensor System (APPSS) problem. I grabbed a small channel-lock pliers and semi-aggressively “tapped” on the accelerator pedal housing. After doing so the coach drove fine. I have a new pedal assembly on order. I’ve had the error occur a couple more times and each time I’ve been able to clear it by banging the accelerator pedal housing, so I’m sure the problem is the pedal assembly. My hope is that this may help another stranded coach driver get to his or her destination in a pinch.
Terry Bush | Pahrump, Nevada
Typically, intermittent problems like this are caused by either bad electrical connections, or components that fail when they heat up and then start working properly again when they cool down. Unfortunately, that covers a lot of items. Often, the trouble code will give some hint in which direction to look for the problem, but in your case until the Chevy service manager checked it, you didn’t have much to go on. What I usually do if a faulty sensor is suspected is try to “exercise” it by cycling it during testing. In this case, you could try repeatedly revving it up (from idle to say 3,000 rpm) in park (brakes set, wheels chocked) and see if it does anything odd. The sensor can also be monitored on an oscilloscope. It can also be very helpful to Google the trouble code along with the model vehicle and see what comes up. Often other folks have already had and solved the problem. Thanks for writing, I’m including your letter because it may help others fighting similar gremlins. Let’s hear from you again after you have the new pedal assembly in for a while.
My 2003 Monaco Diplomat has a 7.5-kW Onan diesel genset (purchased new), presently with 830 hours of run time. During a trip in 2014 (660 hours), the genset started to exhibit intermittent shutdowns. The problem continues, although less frequently, since I did two things to try to fix it: I cleaned all battery ground connections to the chassis and to the genset, and installed a new Magnum pure sine wave inverter/charger. The fault code for every shutdown is 11, which indicates the genset is sensing a current overload. There are no indications of any problems with any 120-volt AC appliances, no circuit breakers opening, and no issues with shorepower. The genset will always restart after any such shutdown and may run under load for as little time as one minute or for very long cumulative periods (including several normal shutdowns) before another code 11 shutdown occurs. I kept a detailed operating log since mid-2015 that notes run time with virtually every 120-volt AC appliance in the motorhome and under various ambient conditions, and there is no correlation between current load and/or appliances running and the code 11 shutdowns. Any idea what is causing these intermittent code 11 shutdowns?
Edward Proctor | Via email
I want to make sure you are clear on how to obtain codes, because based on your description of the situation, it appears that overheating may be a factor. Let’s start with the basics. One blink indicates shutdown due to high temperature, two blinks indicates shutdown due to a loss of engine oil pressure and three blinks indicates shutdown due to some other abnormal condition. Fault Code Nos. 1, 2 and 3 are first-level faults. Avoid interpreting them as second-level Fault Codes 11, 22 and 33. The pauses between repetitions of the fault codes are longer than the pauses between the tens and units digits of the code. For example, Fault Code 33 would appear as:
blink-blink-blink — pause — blink-blink-blink.
With a 13-year-old cooling system, it’s very possible that the system is not working up to par. Check for cleanliness and verify cooling system operation before going further.
If you suspect that certain appliances are drawing too much current, you can measure current load of appliances with a clamp-on ammeter that goes around the wire. You may want to have an electrician chase this down for you. However, the high draw should trigger circuit protection. If you still can’t find the problem I also recommend contacting Onan; I have found its telephone answering tech staff at 800-888-6626 very knowledgeable and helpful.