How to Retrieve and Translate ABS Fault Codes (Anti Lock Brakes) using the Diagnostic Connector on Mk1 (NA) & Mk2 (NB) MX5 Miata Eunos 1989 to 2002 Models.
Retrieving ABS Fault Codes
In the video below I show you how to read Anti Lock Brakes (ABS) fault codes yourself, using the diagnostic connector and a piece of wire, or even a simple paperclip. A summary of the steps taken in this video are shown underneath for those confident enough to get started right away.How to Retrieve ABS Fault Codes
Summary of Steps:
1. To check DTC (Diagnostic Trouble Codes) on the Mazda MX5 ABS system; turn ignition switch to the off position and bridge the TBS and GND terminals in the DIAGNOSTIC socket under the bonnet (see the Diagnostic Connector photo below), using a jumper wire or paperclip.
2. Turn the ignition switch to on and wait for the ABS dashboard indicator to extinguish and count the groups of flashes on the ABS lamp. Long flashes count tens, short flashes count units.
3. Multiple codes will be output one after the other, and then repeat. Once all ABS DTC codes have been output, turn off the ignition switch, remove the jumper wire from the connector and refer to the listing of diagnostic codes below to ascertain the indicated fault(s).
The Diagnostic Connector
Cars built prior to 2002 have a useful Diagnostic Connector located under the hood, above the wing, as shown in the picture below. You can use this diagnostic connector to trace a number of faults in a number of different systems, including; Engine fault codes, ABS (Anti-Lock Brakes), and any faults related to the cars Supplementary Restraint System (Airbags etc). You can do this yourself, without the need for any special scanners, or a costly visit to your local Mazda dealer.
Cars built after 2002 (and sometimes earlier in other parts of the world) are fitted with an OBDII Connector located at the top of the cabin fuse box, underneath the steering wheel. An OBDII Scan Tool is required to read and clear the error codes on these cars.
OBD Connector Pin Out Diagram
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| Connect Jumper Wire Between GND and TBS |
Translating ABS Fault Codes
Use the information below to look up the meaning of any outputted fault codes from your Anti-lock Braking System. Codes will be output once the ABS dashboard indicator light extinguishes for the first time, and will then shown as a series of long and short flashes. Count the number of long flashes, these are the tens, then count the short flashes, the units. Two long flashes followed by one short flashes would indicate fault code 21. Multiple codes are output one at a time, separated by a pause.ABS Diagnostic Trouble Codes;
05 - Brake Switch open circuit
11 - Right Front Wheel Speed Sensor Open circuit or Short to power supply
12 - Left Front Wheel Speed Sensor Open circuit or Short to power supply
13 - Right Rear Wheel Speed Sensor Open circuit or Short to power supply
14 - Left Rear Wheel Speed Sensor Open circuit or Short to power supply
15 - Wheel Speed Sensor, Sensor Rotor
22 - Front Right Solenoid Valve Signal (AV)
23 - Front Right Solenoid Valve Signal (EV)
24 - Front Left Solenoid Valve Signal (AV)
25 - Front Left Solenoid Valve Signal (EV)
26 - Rear Solenoid Valve Signal (AV)
27 - Rear Solenoid Valve Signal (EV)
41 - Right Front Wheel Speed Sensor Rotor Short to ground or Disagreement with other sensors is detected
42 - Left Front Wheel Speed Sensor Rotor Short to ground or Disagreement with other sensors is detected
43 - Right Rear Wheel Speed Sensor Rotor Short to ground or Disagreement with other sensors is detected
44 - Left Rear Wheel Speed Sensor Rotor Short to ground or Disagreement with other sensors is detected
51 - Valve Relay fault
53 - Motor monitor fault
61 - ABS Control Module fault
63 - ABS Module Power Supply Malfunction
Clearing ABS Fault Codes
Most (but not all) ABS fault codes will remain in memory until they are cleared. It is a good idea to clear all codes before starting to diagnose faults, to ensure all codes are current.To clear all fault codes from the ABS system, wait until all codes have been output (they will repeat) and then depress the brake pedal ten times in less than 10 seconds. Turn off the ignition and remove the jumper cable (or paperclip) from the diagnostic connector. You should then start and drive the car a short distance to refresh any faults that may be discovered by the ABS ECU (Electronic Control Unit).
If you find a persistent fault with your Anti-Lock Brakes, you may find the following article on ABS Fault Diagnosis and Repair helpful.
Did you find this article useful? Have a tip for reading ABS fault codes? Please leave a comment below.