Friday, November 18, 2011

Field Testing The Boost Solenoid

At first notice you would tend to think that the only function of the Boost Switch is to boost the engine battery voltage during the main engine start cycle, but, the switch also has a locked “ON” position that allows the house charger to transfer charging voltage to the engine batteries when you don’t have the option of starting and running the main engine for any significant period on a regular basis.

When the boost switch is activated there is a light in the switch that should come on. If the light does not come on when the switch is activated this does not mean that the boost circuit is inoperative, the light is an indicator that the switch is in the “on” position. If the light is out it simply means the switch bulb should be replaced.

Follow the sequence below to check the basic operation of the boost solenoid:

1) Locate the voltage meter in your dash gauge panel. This volt meter indicates the engine battery voltage any time the ignition key is on.

2) Hook coach to shore power

3) Check that the house battery charger is on and charging the house battery, the voltage range of the house batteries while charging will typically be between 13.2 to 14.0 volts, this is indicted on most coaches at the inverter control panel or on the dash monitor screen.

4) With the boost switch in the “off” position, turn the ignition key to “on” without starting the coach.

5) Note the reading of the volt meter on the dash gauges at this point. With fully charged engine batteries the voltage should read in the 12.0 to 12.8 volts range. This reading will be lower if the engine batteries are discharged.

6) With the ignition key remaining in the “on” position activate the boost switch. Watch the voltage on the dash gauge for a few seconds. There should be a noticeable rise on the voltage gauge, if the voltage does rise; the boost circuit is most likely working as it should. If the voltage does not rise and remains static, it could indicate the boost solenoid needs replacement.

If you do suspect a problem in the circuit contact our service department for an appointment and they will be able to confirm there are no other issues in the circuit and determine if the solenoid requires replacement.
To order a solenoid from our parts department contact 1-800-955-6226 option # 3 and they will be able to get you the proper solenoid for your year model coach.

Also, the next time you are in Nacogdoches for service whether you suspect boost system problems or not make sure you ask our service department about having them install a voltage sensitive relay which will allow your system to charge the engine batteries automatically when hooked to shore power or generator. This will eliminate the need for manual boost switch activation, and can be installed on most all year model Foretravel coaches.

Remote Battery Disconnect

All Foretravel’s have a battery disconnect switch and since 2003 many of the coaches began to utilize a remote controlled relay to complete the disconnect via a switch located near the entry of the coach. These are momentary switches meaning you are to push and release either up (on/connect) or down (off/disconnect). When the green LED light at the top of the switch plate is illuminated the batteries are connected.

The remote switch controls a solenoid hidden away in one of the large storage bays. On most coaches the solenoid will be located in the component bay where you will find many of the major chassis related electronic components such as the HWH pumps and control modules, inverter, shoreline transfer relay and automotive circuit panel.

If you discover a problem with the disconnect system many times it is that the 4 amp circuit breaker for the control circuit located around the top of the solenoid has tripped and needs to be reset.

Often the reason for the breaker being tripped is that the remote switch was held in one position too long or possibly someone leaning against the switch while in the doorway.
Locate the 4 amp breaker and reset by pressing the button on its top side and test by momentarily pushing the entry switch to the “up” position and release if the green light comes on, your interior 12 volt supply will be restored.

Tuesday, February 15, 2011

Room Positioning for Checking Oil Level in the HWH Hydraulic Reservoir

If your coach is a 2000 year model or later and you have slide room extensions checking the proper level of the reservoir depends on the type of extension mechanisms used in your particular year model coach. When adequately filled, the oil level of the reservoir will be approximately one inch below the top of the reservoir. All Foretravel systems are factory filled with Dexron Automatic Transmission fluid.

Year Model
Room Location
Room Position For Checking Oil
2000 to 2001
Living Room
Living Room
Bed Slide
2003 to 2007 (End Unit 6434)
Living Room
Bed Slide
Generator Slide
2007 (Start unit 6435) to Present
Living Room
Bed Slide
Generator Slide

For additional information see the maintenance section of your specific HWH Operator’s manual page(s) MP44.0014, MP45.120G, MP45.5055, MP45.996C or MP45.998C.

Fault Indications and Reset Procedures for the Prosine 2.5 Inverter

There are still many of you traveling around the country in earlier model coaches that have a Prosine 2.5 Inverter/Charger. These units were installed as original equipment on coach year models 1999 through 2005. If you encounter a fault condition with this particular Inverter/Charger here is some information that may be helpful.

When a recoverable fault occurs usually there will be an indication on the Prosine Interior Remote Control panel.

Control Panel Indication
Fault Condition
16.75 Volt LED and Warning Light blinking
Battery Voltage Too High
10.00 Volt LED and Warning Light blinking
Battery Voltage Too Low
400 Amp LED and Warning Light blinking
Battery Current Too High, probable AC Overload
Warning, Fault, Temp LED’s blinking
System Over-temperature
Warning, Fault LED’s blinking
Communications error or temporary fault

For fault conditions that don’t appear to correct themselves, you can power down the Prosine Inverter/Charger and reset it by sliding the “BYPASS/ON” switch located on the side of the inverter chassis to the “BYPASS” position, wait for a few seconds, and then switch it back to “ON”
NOTE: The “BYPASS/ON switch is very delicate and is not readily visible from a distance, use every caution not to damage the switch while attempting a reset.

If the fault is not corrected by this method, it may be that battery power input will need to be disconnected, to accomplish a battery disconnect reset:

1)      Turn off the battery charger and inverter on the interior control panel
2)      Slide the “BYPASS/ON” switch to the “BYPASS” position.
3)      Disconnect the DC Negative battery cable from the base of the Inverter chassis.
4)      Wait 15 minutes
5)      Reconnect Negative battery cable
6)      Slide the “BYPASS/ON” Switch back to the “ON” position.
7)      Reconnect shore power if available and check to see if faults are cleared.

After attempting these resets, if the unit still does not operate or has continuous fault indications it should be taken to a qualified service center for further diagnosis.

Friday, August 27, 2010


Many times we forget that even though we live in an age that nothing seems impossible, some things as far as motor home enthusiasts are concerned are not possible. One of those things is cooling performance of an absorption unit versus the compressor driven unit that you may have in your home.

The absorption units that are in most motor coaches are in fact designed to conserve as much energy as possible. But, they also perform very well when properly maintained. While “camping” is not what it used to be, it is now a word that is all but obsolete with the luxuries that time has afforded motor coach owners. For a motor coach to be completely self sufficient, there is a need to conserve on board resources as much as possible, hence the need for a refrigerator that can operate on two or three different sources efficiently.

The refrigerators that are in coaches today are a much more sophisticated machine than the compressor driven units we have at home, where you plug them into an isolated 15-amp 110VAC circuit. These home units are very power-hungry as compared to the units you have in your motorhome. When running on AC voltage, absorption units only draw about 2.5 to 3.0 amps. The absorption unit actually extracts the heat from inside the food compartment slowly. Once the heat is removed, all that is left is cooler air.

There are a few simple steps that can help you get the most out of your refrigerator.

1. Start the refrigerator the day before it is to be filled with food.

2. When the refrigerator is being filled when preparing for a trip, the frozen foods should be pre-frozen before placing them in the refrigerator. Ice making should be avoided until the refrigerator has cooled the lower compartment to the desired temperature.

3. Air circulation within the food compartment is important for proper cooling. DO NOT place paper on the shelves or overfill the compartment with large cartons, etc.

4. Do not put hot food in the refrigerator. Allow it to cool to room temperature first.

If you believe your unit is not cooling as it should, one check you can perform is to check the doors for proper sealing. A simple method of doing this is to close the door on a dollar bill, then pull the bill out. If no resistance is felt, the gasket is not sealing properly. This should be done on all four sides of the door (complete length of the gasket). Also check the rear of the unit for any blockage by opening the side vent and look all the way up the rear of the unit to make sure you haven’t got any stowaways such as birds and their nests. If you are not able to see all the way to the roof vent, then remove the roof cover and check the back of the unit as well. Drafting in the rear of the unit is very important for a proper cooling refrigerator.

To test the unit for proper cooling, place a thermometer in a small container of water and place in the center of the main storage compartment. Set the thermostat to it’s maximum position, close the door and run unit on AC power for 10-12 hours, check the thermometer at the end of this period you should have a reading of 36-42 F. If you do not get this temperature then you should contact your nearest service center for repairs.

Also the burner assembly and the flue should be checked and cleaned annually.

Foretravel Alternators and Isolated Battery Charging

Foretravel coaches are equipped with what are termed “externally excited” alternators.

These are not the same alternators used in the large trucks that run on our nation’s highways.

This fact is often misunderstood in a majority of large truck repair shops. Often

Foretravel customers must utilize these shops when they experience charging problems

on the road. Most of these truck repair facilities are only familiar with what are termed “internally excited” alternators which maintain a single bank of batteries (12 volt supplied to the large output post continually).

Foretravel, as well as other coach manufacturers, utilize a battery isolator in the alternator charging circuit. The alternator must be able to maintain two separate banks of batteries, one bank for the house batteries and one bank for the engine batteries, at a particular set voltage.

When a battery isolated system is used, the alternator has to be turned on, excited, from an ignition source. That process is termed “externally excited”. During testing with the main engine not running, there will be no voltage is present on the large positive output terminal of the alternator.

The alternator that Foretravel employs has two large terminals, one positive and one negative, on the back, as well as two small terminals. The two small terminals tell the voltage regulator what to do. One small terminal is labeled DUVAC and the other small terminal is labeled IGN.

The DUVAC terminal monitors (senses) the output voltage. The sensing wire runs from the DUVAC terminal directly to the engine battery side of the isolator on 2000 year model Foretravel’s to present. Earlier models sensed from the remote start panel.

The IGN (ignition) terminal turns on (excites) the alternator to start charging. This circuit is powered up when the ignition key is turned on. The only way the ignition terminal voltage will affect charge output voltage is if no voltage is present. It takes minimal voltage to start the alternator charging (7-7.5 VDC).

When checking the output voltage directly at the alternator while the alternator is charging, the output voltage will read higher than at the batteries. This is because there will be approximately a 1 volt drop from the output terminal of the alternator to the actual charge voltage at the engine battery terminal. This drop occurs in the isolator and associated wiring to the batteries.

Example: When reading the output voltage at the alternator with fully charged batteries and a properly functioning alternator, your readings should be approximately 15 volts dc (+/-), this in turn will allow for a maximum voltage at the batteries to be 14.1 vdc (batteries allowing for a normal 1volt dc drop in voltage through the isolator).

Checking Transmission Fluid Level from the Cockpit

With your Foretravel you are able to check the transmission fluid directly from your pilot seat. Allison Motorhome Series transmissions have an oil level sensor (OLS) that allows the operator to obtain an indication of fluid level from the shift selector. It is important that the proper fluid level in your transmission be maintained at all times because the transmission fluid cools, lubricates and transmits hydraulic power.

In later models there will be two types of push button shift selectors, the WTEC III or the Allison 4th generation (for information on earlier models shift selectors contact Foretravel Technical services).

WTEC III Controls displays fluid level Allison 4th Generation Controls displays

diagnostic information one character at fluid level diagnostic information two

a time. characters at a time.

1) Park the vehicle on a level surface, shift to N (Neutral), and apply the parking brake.

2) On the push button shift selector simultaneously press the↑ (Up) and ↓ (Down) arrow buttons.

NOTE: The fluid level check may be delayed until the following conditions are met:

• The fluid temperature is above 140°F and below 220°F.

• The transmission is in N (Neutral).

• The engine is at idle.

• The transmission output shaft has stopped.

• The vehicle has been stationary for approximately two minutes to allow the fluid to settle.

A delayed fluid level check for transmissions with WTEC III controls is indicated by a (-) DASH in the display window followed by a numerical countdown. The countdowns start at 8, indicates the time remaining in the two minutes setting period. The delayed indication for Allison 4th Generation is indicated by a flashing display under SELECT and a digit countdown from 8 to 1 above MONITOR.

• Correct Fluid Level – “o L” (represents “Fluid (Oil) Level Check Mode”) followed by “o K”. The “o K” indicates the fluid is within the correct fluid zone. (The OLS display and the transmission dipstick may not agree exactly because the OLS compensates for fluid temperature.

• Low Fluid Level – “o L” followed by “L o” (represents “Low Oil Level”) and the number of quarts the fluid is low. Example: o L L o 0 2 indicates fluid is low by 2 quarts.

• High Fluid Level – “o L” followed by “H I” (represents “High Oil Level”) and the number of quarts the fluid is high. Example: o L H I 01 indicates fluid is above the full level by 1 quart.

Any temperature below 140°F or above 220°F will result in an Invalid for Display condition. See your Allison Operator’s Manual for more info on this condition and complete details on checking transmission fluid.