This kit covers 1985 to 1992 Hondas and during these years the Honda ECUs went through some major revisions. The early ECUs had four LEDs. Each LED had a different value (1, 2, 4, 8). If the Check Engine light came on, the computer displayed the code without requiring a switch over to a diagnostics mode.

All you do is observe the LEDs and add up the values of the lights. So the number 2 LED on means code 2. The number 4 and 2 illuminated means code 6 and so on. Later ECUs flash in short and long duration bursts. Short bursts for single digit while a long burst is the first digit of a two-digit code. Some 1991 and all 1992 and up ECUs use a jumper wire to initiate code reading and use the short/long flash method.

It should be noted that all codes must be erased after repairs and the manual details these procedures for each make.

Deciphering The Code
Breaking the code is only part of the battle. Deciphering the meaning of the numbers you have retrieved will allow you to pinpoint the problem area. The manual breaks down the codes and gives an insight into what may be wrong.

We have listed baseline codes in the accompanying chart for imports only because there are dozens of ECU and transmission codes for Ford and GM products and not enough room here to even come close to providing an overview of the pertinent number groups.

Component Diagnosis
Diagnosing is a chase wherein you box in the problem by eliminating possibilities and pinpointing the component that is faulty.

The included Sensor Tester is used to check codes that lead to the TPS, EGR, O2, Temperature, Knock and Hall Effect sensors as well as ignition modules. The Sensor Probe is used to identify problems in MAP, MAF or Vein Airflow sensors.

The Multimeter reads DC volts, resistance, and current draw and has high tech and low tack scales as well as dwell in degrees and duty cycle in percentage. It can be used to check the health of the electrical system, confirm if switches, solenoids and relays are functioning properly. It can verify that ignition coils and wires, fuel injectors and a number of other sensors are in working order.

If you are rolling an OBD-I-equipped car this kit hits the bull's-eye. While we cover the basics here, we cannot rave enough about the info in the manuals and on the videos; it puts forth the proper information in an easy-to-understand manner. The kit gives enthusiasts the Sherlock Holmes intuition needed to narrow down the suspects and flush out the guilty party when it comes to the smooth running of their car. Next time our Diagnostics section will address the code breaking needs of OBD-II cars.