sure; check gasket for damage. (Monthly)-Clean manhole gasket and
lubricate clamps.
2. Lights and Wiring-(Daily)-check all lights for proper operation.
(Weekly)-Check all connections. (Every 5000 miles)-Check for chafed
or broken wires.
3. Anti-Lock Brake System-(Daily)-Check for proper operation. Refer
to Anti-Lock System Maintenance Manual. (Every 5000 miles)-Adjust
brakes, see page 50. (Every 10,000 to 25,000 miles)-Inspect linings,
free-up brake shoes and anchor pins.
4. Rear Structure-(Weekly)-Check bolts for proper torque (150 ft-lbs)
5. Suspension-(Every 5000 miles)-Check for proper bolt torque. See
page 71 for torque chart.
6. Tires-(Daily)-Check for proper inflation, cuts or other damage. See
page 61.
7. Axles-(Weekly)- Check oil level and for leakage around oil seals, see
page 58. Recommended hub oil is Synthetic 75W-90. Recommended
hub grease is Mobilith 007 and Chevron Delo. Check pivot bolt
connections for proper torque. (Every 5000 miles) Check axle
alignment to king pin, see page 63. Do not mix oil with grease.
8. Wheels-(Weekly)-Check lug nuts or bolts for proper torque, see page
62. (Every 10,000 to 25,000 miles) Check wheel bearings. Tighten or
replace as required. See page 58.
9. Aeration -Clean or replace as required. (Every 2 years)
10. Piping-Check for loose clamps, damaged hoses or leaks. (Monthly)
Perform general inspection.
11. Supports-(Monthly)-Lubricate; check mounting bolts for proper
torque (150 ft-lbs).
12. Front Structure-(Weekly)-Check bolts for proper torque (150 ft-lbs).
13. Landing Gear - (At least every 3 months) - Lithium Base 1-2% Moly
EP-2. For temperatures less than –50 use Artic-Grade all weather
white grease.

46

LUBRICATION AND SERVICE (CONTINUED)
14. Upper 5th Wheel-(Every 5000 miles) Lubricate with multipurpose
grease.
15. Compressor or Blower-Service according to manufacturer’s
recommendations.

GENERAL INSPECTION-AERATION SYSTEM
The following inspection should be performed monthly.
1. Check pressure gauges for accuracy.
2. Close manhole covers. Close all valves except aeration valves.
Remove dust cap from product line.
3. Start compressor (or blower) and pressurize tank until relief valve
opens. DO NOT EXCEED MAXIMUM OPERATING PRESSURE

WARNING
If relief valve does not open at pressure specified on valve, shut off
compressor or blower and correct the cause of the inoperative relief
valve. See Page 43 for testing Relief Valve.

NOTICE
Compressors can be severely damaged if operated at speeds and
pressures higher than rated and if the air filter is clogged. Check
operating speed and pressure rating of the compressor to make sure it
is not running too high. See Manufacturer’s recommendations.

4. After tank is pressurized, close the aeration valves and shut off
compressor blower. Tank pressure should remain relatively
constant. If pressure drops excessively, check for leaks in manhole
cover, relief valve, blow-down valve and tank proper. If none are
found with the above inspection, check for air leaks in the aeration,
pressure control and product valves.

47

5. When inspection is complete, open blow-down valve to exhaust the air
in the tank. Replace dust cap on product line. If one or more hoppers
does not discharge properly, and there are no leaks in tank or valves,
the following service procedure is recommended.
1. Remove product from these sections.
2. Check aeration line for possible plug.
3. Check aeration device on interior of tank. Look for torn molded
neoprene cone(s), rotated wear plate(s) or plugged aerator
housings (see Figure 10). Replace as necessary.

Figure 10. Exploded View of Aerator

48

Vacuum/Filter Maintenance
Cleaning Instructions
1. Close the top cyclone cleanout valve (bottom valve should remain closed).
2. Open both cleanout ball valves and allow the line to clear.
3. Close the cleanout ball valves.
4. Open the bottom cyclone cleanout valve.
Filter System Maintenance
Normal maintenance suggested for all filters is a three part process:

Backflushing

Inspection

Cleaning

Every load / unload
cycle

Every 2 months

Every 6 months

Reverse the flow of blower air from clean side
to filtered side to “flush” loose filtered particles
from the filter element and improve perfor-

Remove filter retainer plate. Randomly remove and visual inspection filter elements for
damage.
Backflush filter elements with an air nozzle.
Wash with warm water (max 80oC/175oF)
and mild household detergent. Upon reassembly run blower air through filter to dry the
elements.

For inspection, cleaning and ease of
handling, the filter assembly can be removed
by removing the (12) 3/8” locknuts on the
outside radius and then using the lift handle
in the center of the filter to remove.
The retaining is removed by the inner radius
of locknuts.
Note: Install rubber grommet with each
element and be sure it is seated in the plate
prior to reassembly.

49

BRAKES-MAINTENANCE & ADJUSTMENT
NOTICE
For more information reference the manufactures web literature or call their
customer support.
The wheel brakes are equipped with slack adjusters for easy brake adjustment to
compensate for brake lining wear. It is recommended that slack adjuster arm
travel be held to a minimum for most efficient braking action. The brakes should
be adjusted when total arm travel reaches 1-1/2”.
To adjust brakes, depress lock sleeve on slack adjuster, then turn adjustment
screw as required. Make sure lock sleeve returns to lock position when adjustment is complete.
Every 5000 miles, the brake camshafts should be lubricated with approved
chassis lubricant. Every 10,000 to 25,000 miles, the brakes should be serviced
as follows:
1. Remove wheels and hubs.
2.

Inspect brake roller shafts, cam rollers, anchor pins, camshaft support
bushings, spider bushings and camshaft for wear and replace if necessary.
Lubricate these parts with chassis lubricant upon reassembly.

3. Inspect brake linings for wear, loose rivets and any signs of grease on the
braking surface. Oil-soaked linings are not reusable and must be replaced.
Check to ensure that the linings have not worn to the point that rivet heads
are contacting inside surface of drum. Reline or replace brake shoes if
necessary.
4. Check inside surface of drum. Rebooting of drums is not recommended, as
the strength of refaced drums is greatly reduced. If drum is worn, replace it.
5.

Service the wheel bearings and seals if required. Reassemble hubs and
wheels.

50

DISC BRAKE INSPECTION & PREVENTIVE MAINTENANCE
Basic Inspection w/ wheel mounted
1. For vehicles with electronic wear indicators, use the dash indicator(s) and/or
the hand-held diagnostic tool to regularly monitor the pad wear.
2. In all cases, visually inspect the wear indicator ever three months (or keep
track of the results of maintenance inspections to schedule checks 4 to 5 times
during the pad lifetime). If indicators line up, time to schedule inspection of pads
and rotors.
3. A visual check of the mechanical wear indicator every time the tire pressures
are checked is recommended. Be alert for any rotor cracks, etc. visible.
4. Follow all industry safety guidelines. On level ground, with the wheels chocked
and the parking brake temporarily released, check for movement of the brake
caliper. This small movement, less than 0.80" (2 mm) approximately the
thickness of a nickel - in the inboard/outboard direction indicates that the
brake is moving properly on its guide pins. If the caliper has no movement or
appears to move greater than the distances above, a full wheel-removed
inspection will be necessary.
Basic Inspection w/ wheel removed (annually and at pad replacement)
1.
2.
3.
4.
5.

Inspect
Inspect
Inspect
Inspect
Inspect

the rotor for cracks, etc.
the running clearance and adjuster function .
the caliper travel.
the tappet and boot assemblies.
all covers, caps, hoses and brake exterior for damage etc.

Figure 11. Pad Indicators

51

ROLLOVER PROTECTION AND ABS

INTRODUCTION

The rollover protection available on Heil trailers is an electronic, self-monitoring
system that works with standard air brakes to enhance the safety and reduce the
potential of trailer rollover accidents. Electronic rollover protection systems
monitor many factors that may cause a rollover accident; vehicles speed, wheel
speed, air suspension pressure, and lateral acceleration along the vehicles roll
axis. Rollover protection activates when one or more factors exceed safe conditions. The trailers stability is achieved by the rollover device sensing unsafe
conditions or speeds and sending a signal to the Electronic Control Unit (ECU),
where it reduces the vehicles speed to a “safe” range. All data may be looked up
from the information centers or by hooking up a diagnostics tool.

DANGER

IT IS IMPORTANT TO NOTE THAT THE TRAILERS “ROLL STABILITY SYSTEM” IS MERELY A
LIMITED ASSIST TO MINIMIZE ROLLOVERS UNDER CERTAIN SITUATIONS AND IS NOT
INTENDED TO NOR WILL IT PREVENT ROLLOVERS IN ALL SITUATIONS, AND MORE
PARTICULARLY, THOSE RESULTING FROM DRIVER ERROR OR INSUFFICIENT TRAINING
OR EXPERIENCE, IMPROPER TRAILER CONDITION AND LOADING, EXCESSIVE SPEED FOR
CONDITIONS, ROAD DESIGN INCLUDING EXITS, ROAD DEBRI AND HAZARDS SUCH AS
OTHER VEHICLE ACCIDENTS, WEATHER CONDITIONS, IMPROPER ABS, BRAKE COMPONENT AND WHEEL MAINTENANCE, IMPROPER TIRE CONDITION AND REPLACEMENTS AND
OTHER CONDITIONS WITHIN OPERATOR CONTROL AND OBSERVATION FOR ASSESSING
POTENTIAL ROLLOVER CONDITIONS AND HAZARDS WHICH COULD POSSIBLY LEAD UP TO
A POTENTIAL ROLLOVER RESULTING IN, PERSONAL INJURIES, FATALITIES AND ENVIRONMENTAL AND PROPERTY DAMAGE.

INSTALLATION
Refer to CD supplied with tank for installation diagrams, procedures and Plumbing
Schematics. These drawings are trailer specific.

Common Types of Trailer Rollover Protection and ABS
>Haldex. Trailer Roll Stability (TRS)
>Meritor WABCO. RSSplus Trailer ABS with Roll Stability
>Bendix. Bendix ABS with ESP (Electronic Stability System)

52

ROLLOVER PROTECTION AND ABS
NOTICE
Remove all air pressure and electrical power from the brake system
before beginning any work on system.

DIAGNOSTICS/TROUBLESHOOTING
Most ABS or Roll Stability problems are related to:
1. Cut, corroded, or abraded wires.
2. Corroded connectors and terminals.
3. Connector terminal not latched or seated correctly to mating assemblies.
4. Excessive sensor air gap, sensor clip retention.
5. Wheel bearing end play.

Faults, problems and diagnostics are displayed two different ways. When the
system detects an issue it alerts the driver/owner by either delivering a Blink
Code Count to the ABS indicator lamp located on the rear streetside fender
(Figure 13) or by sending a fault code to an information center (Figure 12)
located on the rear frame of the trailer.

Figure 13. ABS indicator Lamp

Figure 12. TRS Info Center 2

Note: Data collected when the system detects a fault will be stored and can be
retained with proper diagnostic tool.

53

ROLLOVER PROTECTION AND ABS

DIAGNOSTICS/TROUBLESHOOTING

Diagnostic Trouble Fault Codes List (HALDEX)

Power Supply Fault Code List
ECU TIME OUT or NO LINK

No supply on ignition switched line. Check truck fuses, 7-way
connection, 5-way ABS connection, power cable connections.
Check diagnostic cable for corrosion.

PWR ISO7638 FAILI

Intermittent power loss. Check all electrical connections as
mentioned above.

PWR LO VOLT

Supply voltage < 8 volts. Check voltage regulator on tractor,
loose connections, and corrosion.

PWR HI VOLT

Supply voltage > 17 volts. Same as above.

Sensor/Sensor Extension Fault Code List
Note. The fault code identified which sensor/wheel end needs
to be checked.
S1A
S1B
S2A
S2B

CONT
CONT
CONT
CONT

Open or Short Circuit. 1. Disconnect the sensor extension
cable from sensor and measure electrical resistance between
the two pins in the sensor housing, it should be between 9802350 ohms. 2. Disconnect sensor extension from ECU and
measure continuity.

S1A
S1B
S2A
S2B

SIGNAL
SIGNAL
SIGNAL
SIGNAL

Intermittent low sensor output occurs when vehicle is moving.
Check for broken sensor retaining clip, damaged or misaligned
exciter ring, excessive wheel bearing end play, loose/ damaged/corroded sensor connections or a break inside the sensor cabling.

54

ROLLOVER PROTECTION AND ABS

DIAGNOSTICS/TROUBLESHOOTING

Sensor/Sensor Extension Fault Code List (cont..)
S1A
S1B
S2A
S2B

SIGNAL
SIGNAL
SIGNAL
SIGNAL

Low sensor output. 1. Rotate the wheel at 1 rev / 2 sec and
measure AC voltage at the sensor plug, it should be > 200
millivolts. 2. Make sure sensors are pushed up against exciter rings.

Modulators Fault Code List
BRK APPLY SC
BRK APPLY OC
BRK APPLY SC DRIVE BRK
APPLY UNSPEC

Internal fault with the brake apply solenoid. Detach ECU
and replace modulator.

EPRV 21 HOLD SC
EPRV 21 DUMP SC
EPRV 21 HOLD OC
EPRV 21 DUMP OC
EPRV 21 HOLD SC DRIVE
EPRV 21 DUMP SC DRIVE
EPRV 21 HOLD UNSPEC EPRV
21 DUMP UNSPEC

Internal fault with the hold or dump solenoids of modulator
21. Detach ECU and replace modulator.

EPRV 22 HOLD SC
EPRV 22 DUMP SC
EPRV 22 HOLD OC
EPRV 22 DUMP OC
EPRV 22 HOLD SC DRIVE
EPRV 22 DUMP SC DRIVE
EPRV 22 HOLD UNSPEC EPRV
22 DUMP UNSPEC

Internal fault with the hold or dump solenoids of modulator
22. Detach ECU and replace modulator.

DEMAND SC
DEMAND OC

Internal fault with the service/control line pressure transducer. Detach ECU and replace modulator.

EPRV
EPRV
EPRV
EPRV

21
21
22
22

DEL
DEL
DEL
DEL

SC
OC
SC
OC

Internal fault with the delivery pressure transducer. Detach
ECU and replace modulator.

55

ROLLOVER PROTECTION AND ABS

DIAGNOSTICS/TROUBLESHOOTING

Modulators Fault Code List (cont..)
EPRV 21 SLOW REC
EPRV 22 SLOW REC

Wheels are slow to recover after brakes are released. Make
sure foundation brakes are operating properly, delivery hoses
not pinched, speed sensors not crossed with modulator, correct side-by-side plumbing.

RESR SC
RESR OC

Internal fault with the reservoir pressure transducer. Detach
ECU and replace modulator.

SUSP SC
SUSP OC
SUSP OUT OF RANGE

1. Check for air leaks on suspension lines 2. Make sure leveling valve is plumbed correctly 3. Internal fault with the suspension pressure transducer. Detach ECU and replace modulator.

WARNING
The Roll Stability and ABS is an electrical system. When you work on
the ABS, take the same precautions that you must take with any
electrical system to avoid serious personal injury. As with any
electrical system, the danger of electrical shock or sparks exists that
can ignite flammable substances. You must always disconnect the
battery ground cable before working on the electrical system.

NOTICE
Refer to Anti-Lock Brake System Maintenance Manual for operational
check and service instructions.

56

ROLLOVER PROTECTION AND ABS

DIAGNOSTICS/TROUBLESHOOTING

Blink Code Diagnostics (WABCO)
There are two kinds of faults: active and stored. Active faults are those currently existing in
the system, such as a broken wire. Active faults can be diagnosed through blink codes or
TOOLBOXTM Software. Stored faults are faults that have occurred but do not presently
exist. Active faults can be cleared only after repairs are completed. Stored faults can only be
diagnosed with TOOLBOXTM Software.
The ECU signals a malfunction by lighting both the internal and external indicator lamp
when a fault exists. Blink codes are activated through Ignition Power Activation.

Ignition Power Activation
Ignition Power Activation is the process of
using the vehicle’s ignition switch (or interrupting the power on the blue wire by some
other means) to display blink codes on the
trailer ABS indicator lamp located on the side
of the trailer. This method is for constant
power vehicles only.
NOTE: For ignition power activation, power is
provided by the ignition switch.
To obtain blink codes using ignition power
activation, perform the following procedure:

Blink Code Counts

Component Name

0

No failure

3

Sensor failure c

4

Sensor failure d

5

Sensor failure e

6

Sensor failure f

7

External modulator failure

9

Internal modulator failure H2

10

Internal modulator failure H1