Support

This page includes ABS troubleshooting and blink-code viewing, operating instructions for the base unit and remote, maintenance and care details, and a support FAQ.

If you need any assistance or have questions, please reach out to us at support@merlos.co .

ABS Guide & Troubleshooting

Identify ABS Module

Confirm the trailer’s ABS brand. The Pocket Tester supports Bendix, Meritor (MTR), and Haldex.

Connect Base Station

Plug the tester into the trailer’s 7-way socket and power it on.

Select Module

For Haldex or Meritor, press Haldex/MTR. For Bendix, press Bendix on the remote.

Wait for Signal

The base station sends a request to the trailer’s ABS ECU.

Read Blink Codes

The trailer ABS lamp flashes a pattern indicating faults. Use the brand chart below.

Bendix

Blink CodesDescription
1st Code2nd Code
21–4SL WSS Signal
31–4SR WSS Signal
41–4, 6SAL WSS Signal
51–4, 6SAR WSS Signal
25SL Tire Configuration
35SR Tire Configuration
45SAL Tire Configuration
55SAR Tire Configuration
6AnyPower
7AnyModulator 1 DTC
81–3Modulator 2 DTC
91–3Modulator 3 DTC
84Modulator 2 Configuration Error
94Modulator 3 Configuration Error
10AnyModulator Common
11AnyElectronic Control Unit (ECU)
12AnyJ1587 Diagnostic
13AnyTrailer ABS Indicator Lamp

Note: This chart provides a simplified list of ABS fault codes for quick reference. For detailed diagnostics, advanced troubleshooting, or additional information on this ABS system, please refer to Bendix’s official documentation.

Meritor (MTR)

Blink CodeProblem AreaTroubleshooting
3Sensor BU1Identify the sensor's position and verify its installation.
4Sensor YE1Identify the sensor's position and verify its installation.
5Sensor BU2Identify the sensor's position and verify its installation.
6Sensor YE2Identify the sensor's position and verify its installation.
7External ABS
ABS Modulator Valve		Ensure electrical connections are correct, check the power source.
9Internal Modulator Failure,
Inlet Valve #2		Confirm that installation is correct. If the issue persists, consult the manufacturer’s support.
10Internal Modulator Failure,
Inlet Valve #1		Confirm that installation is correct. If the issue persists, consult the manufacturer’s support.
11Internal Modulator Failure,
Outlet Valve		Confirm that installation is correct. If the issue persists, consult the manufacturer’s support.
14Power SupplyEnsure electrical connections are correct, check the power source.
15ECU FailureConfirm that installation is correct. If the issue persists, consult the manufacturer’s support.
16SAEJ1708 FailureInternal system error. Consult the manufacturer’s support.
17SAEJ2497 (PLC) FailureInternal system error. Consult the manufacturer’s support.
18Generic I/O FailureEnsure electrical connections are correct, check the power source.

Note: This chart provides a simplified list of ABS fault codes for quick reference. For detailed diagnostics, advanced troubleshooting, or additional information on this ABS system, please refer to Meritor WABCO’s official documentation.

Haldex

Blink CodeDescriptionFault CodeTroubleshooting
Stays onSystem OK07System functioning correctly.
1Red Sensor 1A01Check for open or short circuits in sensor wiring. Measure resistance between pins; expected range is 980–2350 Ohms. Verify all connections. Replace faulty wiring if needed.
2Red Sensor 1B02Check for open or short circuits in sensor wiring. Measure resistance between pins; expected range is 980–2350 Ohms. Verify all connections. Replace faulty wiring if needed.
3Blue Sensor 2A03Check for open or short circuits in sensor wiring. Measure resistance between pins; expected range is 980–2350 Ohms. Verify all connections. Replace faulty wiring if needed.
4Yellow Sensor 2B04Check for open or short circuits in sensor wiring. Measure resistance between pins; expected range is 980–2350 Ohms. Verify all connections. Replace faulty wiring if needed.
5Blue Sensor 3A05Check for open or short circuits in sensor wiring. Measure resistance between pins; expected range is 980–2350 Ohms. Verify all connections. Replace faulty wiring if needed.
6Yellow Sensor 3B06Check for open or short circuits in sensor wiring. Measure resistance between pins; expected range is 980–2350 Ohms. Verify all connections. Replace faulty wiring if needed.
7Red Solenoid Valve61, 67
71, 77
81, 87		Inspect the modulator solenoid for open or short circuits. Repair or replace any damaged components.
8Blue Solenoid Valve62, 68
72, 78
82, 88		Inspect the modulator solenoid for open or short circuits. Repair or replace any damaged components.
9Yellow Solenoid Valve63, 69
73, 79
83, 89		Inspect the modulator solenoid for open or short circuits. Repair or replace any damaged components.
10Low Voltage Supply90Ensure power supply to the ABS is stable (>10 V). Verify there are no issues with the power source.
11ECU93, 99
E-Codes		Replace or reprogram the ABS ECU if corrupt memory or hardware failure is indicated.

Note: This chart provides a simplified list of ABS fault codes for quick reference. For detailed diagnostics, advanced troubleshooting, or additional information on this ABS system, please refer to Haldex’s official documentation.

Operating Instructions

Circuit Indicator Lights

When a circuit is turned on, the LED panel will show any defects detected:

  • Green: Output on, no defects
  • Yellow: Open circuit detected
  • Red: Short detected (flashes, then remains red)
  • Purple: Crossed circuit detected
  • Blue: External power detected (tractor mode)
  • All LEDs Flashing Red: Low battery voltage

Local Auto Cycle (Without the Remote)

You can run lighting tests from the base unit using Auto Cycle:

  • Start Auto Cycle: Hold the Battery button for 5 seconds (yellow LED wave)
  • Pause: Press once (red LED wave)
  • Resume: Press once (green LED wave)
  • Exit: Hold the Battery button for 5 seconds

External / Tractor Mode

Used for checking if a tractor or external source is supplying power to the 7-way socket:

  • Turn the Pocket Tester off
  • Plug the tester into a powered 7-way socket
  • Turn the tester on
  • The blue LED indicates external power is detected

Warning: Do not plug the device into a powered socket while a circuit is active or while the device is turned on.

Charging the Base Unit

Only use the supplied 15V charger and charge at room temperature.

  • The LED flashes while charging
  • The LED remains steady once fully charged
  • Charging time is approximately 3 hours

Remote Instructions

One-Click ABS

Press buttons 8 and 9 together to send the ABS test signal (for blink-code ABS trailers).

Hazard Lights

  • Press 3 and 4 together to turn hazards on
  • Press 3 and 4 again to turn them off
  • You can still test other circuits with hazards on

Remote Pairing

Activate Pairing Mode (Base Unit):

  • Turn on the base unit
  • Immediately press and hold the Battery button
  • Orange LED cycles back and forth — pairing mode lasts 30 seconds

Pair the Remote:

  • On the remote, press and hold Buttons 1 and 7 together
  • Hold until all LEDs on the base turn green (successful pairing)
  • If pairing fails, all LEDs turn red

Magnetic Storage

The remote stores securely on top of the base unit using the built-in magnets.

Maintenance and Care

Using Dielectric Grease

Apply a thin layer of the supplied dielectric grease to the 7-way insert pins every few months or as needed. This helps prevent corrosion and extends contact pin life.

Handling and Cleaning

Do Not Submerge: The device is not waterproof; avoid water exposure.

Cleaning: Use a soft, non-abrasive cloth. Avoid harsh chemicals or abrasive materials.

Storage

Carrying Case: Store the device in its case to protect it from dust, impacts, and environmental exposure.

Environment: Keep in a cool, dry place away from direct sunlight, high humidity, and heat sources.

Battery Care

Avoid Extreme Temperatures: Do not expose the device to very high or low temperatures.

Charging Practices: Unplug after full charge and avoid leaving it plugged in for long periods once fully charged.

Support FAQ

Why are the trailer lights dim when the device is plugged in?

This is completely normal. The Pocket Tester sends a small sensing current through the circuits to check for defects. This low current may cause some trailer lights—especially LEDs—to glow dimly. This behavior does not affect normal operation.

Why does it take a long time for the Pocket Tester to charge?

The device charges slowly by design to protect the internal lithium battery and extend long-term lifespan. Fast charging can damage batteries over time. A full charge typically takes about 3 hours.

Why does my remote not work?

Please ensure the remote is fully charged. If it still does not respond, try a soft reboot:

  • Press and hold both the AUTO and BENDIX buttons for a few seconds.

This does not unpair the remote and may resolve minor issues. If problems persist, please contact us at contact@merlos.co.

Why are all LEDs flashing red?

All LEDs flashing red indicates the device has activated battery protection. This may occur when:

  • The battery is too low to safely power trailer lights
  • An overcurrent condition occurred (e.g., positive-to-ground short while a circuit is active)
  • The device is protecting internal components from damage

Recharge the Pocket Tester before resuming use.



If you have any questions or concerns, please contact us at support@merlos.co.