To cause the ECU to flash the error codes on
the MIL, With the car turned off, open the diagnostic
connector box and bridge the terminals named "TEN" and "GND" with a wire The terminals are
labeled under the cover of this box. The Diagnostic connector is located Beside the battery it is a little
black box with the word "diagnosis" engraved on it.
1-Start with the ignition off.
2- Then turn your key to the "on" position and count the
flashes.
To clear the error codes,
1- Disconnect the negative battery cable for at least 20 seconds.
2- Depress the brake pedal.
3- Re-connect the battery cable.
In the "pattern" column below, the "L"
stands for a long flash, and the "S" stands for a short flash. | Code | Pattern | Problem | Memorized |
| 02 | SS | Crank
angle sensor no NE signal |
Yes |
| 03 | SSS | Crank
angle sensor no G signal |
Yes |
| 05 | SSSSS | Knock
sensor open or short circuit |
Yes |
| 06 | SSSSSS | Speedometer sensor | Yes |
| 09 | SSSSSSSSS | Water
Thermosensor open or short circuit |
Yes |
| 11 | L S | Intake
Air Thermosensor open or short circuit |
Yes |
| 12 | L SS | Full Range Throttle sensor open or short circuit | Yes |
| 13 | L SSS |
Pressure Sensor open or short circuit |
Yes |
| 14 | L SSSS |
Atmospheric pressure sensor (in ECU) open or short circuit |
Yes |
| 15 | L SSSSS | Oxygen
Sensor less than .55v for more than 120 sec in feedback mode |
Yes |
| 16 | L SSSSSS | EGR
Switch open or short circuit |
Yes |
| 17 | L SSSSSSS |
Feedback System No change for 25 sec in feedback mode |
Yes |
| 18 | L SSSSSSSS | Narrow
Range Throttle Sensor open or short circuit |
Yes |
| 20 | LL |
Metering Oil Pump Position Sensor open or short circuit |
Yes |
| 23 | LL SSS | Fuel
Thermosensor open or short circuit |
Yes |
| 25 | LL SSSSS |
Pressure Regulator Control Solenoid open or short circuit |
No |
| 26 | LL SSSSSS |
Metering Oil Pump Stepping Motor open or short circuit |
No |
| 27 | LL SSSSSSS |
Metering Oil Pump Sensor open or short circuit or MOP sticking |
Yes |
| 28 | LL SSSSSSSS | EGR
Solenoid open or short circuit |
No |
| 30 | LLL | Split
Air Bypass Solenoid open or short circuit |
No |
| 31 | LLL S | Releif
1 Solenoid open or short circuit |
No |
| 32 | LLL SS |
Switching Solenoid open or short circuit |
No |
| 33 | LLL SSS | Port
Air Bypass Solenoid open or short circuit |
No |
| 34 | LLL SSSS | Idle
Speed Control Solenoid open or short circuit |
No |
| 37 | LLL SSSSSSS |
Metering Oil Pump low battery voltage |
Yes |
| 38 | LLL SSSSSSSS |
Accelerated Warmup System Solenoid open or short circuit |
No |
| 39 | LLL SSSSSSSSS | Releif
2 Solenoid open or short circuit |
No |
| 40 | LLLL | Purge
control Solenoid open or short circuit |
No |
| 42 | LLLL SS | Turbo
Precontrol Solenoid open or short circuit |
No |
| 43 | LLLL SSS |
Wastegate control Solenoid open or short circuit |
No |
| 44 | LLLL SSSS | Turbo
control Solenoid open or short circuit |
No |
| 45 | LLLL SSSSS | Charge
control Solenoid open or short circuit |
No |
| 46 | LLLL SSSSSS | Charge
Releif Solenoid open or short circuit |
No |
| 50 | LLLLL | Double
Throttle control Solenoid open or short circuit |
No |
| 51 | LLLLL S | Fuel
Pump Relay open or short circuit |
No |
| 54 | LLLLL SSSS | Air
Pump Relay open or short circuit |
No |
| 71 | LLLLLLL S | Front
Secondary Injector open circuit |
No |
| 73 | LLLLLLL SSS | Rear
Secondary Injector open circuit |
No |
| 76 | LLLLLLL SSSSSS | Auto
Tranny Lockup Signal open or short circuit |
No |
| 77 | LLLLLLL SSSSSSS | Auto
Tranny Reduce Torque Signal open or short circuit |
No |
If more than one failure is
present, the codes will be indicated in numerical order,
lowest number first.
How To pull ECU CODES for your 1988 -1991 RX7
If your check engine light is coming on at idle you need to find out what it is telling you.
To do so for RX-7's from 1988 on, (with the engine off but fully warmed up) find the single green wire in the wiring harness just in front of the left front suspension tower, near the front ignition coil.
Ground the connector on this wire (the wire will be hanging free, without its connector hooked to another wire) on the chassis, using a jumper wire, etc.
Sit in the car and turn the ignition switch on WITHOUT STARTING THE CAR. Immediately watch the check engine light. If everything is OK, it will not light. If it starts flashing, count the flashes. It may stop flashing for a couple of seconds, then start again. Each of those series of flashes is for a separate engine fault code. Multiple codes will display in order from low number to high.
Have a paper and pen handy, and write them all down. To check again, turn the ignition off and then back on. It will repeat the cycle.
Identify the first (tens) and second (ones) digits of each code as follows: The first (tens) digit will display (flash) for about one second for each count, with a one-half second pause between counts. For example, if the first (tens) digit is three, there will be three separate one second long flashes, separated between by one-half second pauses.
There is then a 1.6 second pause between the last flash of the first digit and the beginning of the second (ones) digit.
The second (ones) digit counts flash for only one-half second each, with pauses of one-half second between them. For example, if the second (ones) digit is seven, then there will be seven flashes of one-half second, separated by pauses of one-half second.
In this example, the displayed code will thus be "37".
The system will then pause for four seconds before proceeding to the next code, if any.
To clear the stored codes from memory, disconnect the negative battery cable, then wait for 5 seconds. It is useful to do so even when you have just retrieved the codes, but not fixed anything yet, to be certain the codes (problems) persist. Stored codes could represent several different problems that have arisen at different times. Just drive the car a bit, and see which codes persist.
Obviously, once things are fixed, you need to clear the codes a final time to be certain it is in fact fixed, and to know that any new stored codes have occured after the fix.
Mazda RX-7 codes (from Haynes Computer Codes Manual #10205) are as follows:
1 Ignition coil (trailing side) 2 Crank position NE sensor 3 Crank position G sensor 5 Knock sensor 8 Airflow meter (AFM) 9 Water thermosensor 10 Intake air thermosensor (AFM) 11 Intake air thermosensor (engine) 12 Throttle sensor - full range 13 Pressure sensor - intake manifold 14 Atmospheric pressure sensor (built in ECU) 15 oxygen sensor 17 Feedback system for O2 sensor 18 Throttle sensor - narrow range 20 Metering oil pump position sensor 23 Fuel thermosensor 25 Solenoid valve - pressure regulator control 26 metering oil pump stepper motor 27 Metering oil pump 28 Solenoid valve - EGR 29 Solenoid valve - EGR vent 30 Solenoid valve - split air bypass 31 solenoid valve - relief 1 32 Solenoid valve - switching 33 Solenoid valve - port air bypass 34 Solenoid valve -idle speed control (BAC) 37 Metering oil pump 38 Solenoid valve - accelerated warmup system and air supply valve 39 Solenoid valve - relief 2 40 Solenoid valve - purge control (auxilary port valve) 41 Solenoid valve - variable dynamic effect intake (VDI) 42 Solenoid valve - turbo precontrol 43 Solenoid valve - wastegate control 44 Solenoid valve - turbo control 45 Solenoid valve - charge control 46 Solenoid valve - charge relief control 50 Solenoid valve - double throttle control 51 Fuel pump relay 54 Air pump relay 65 Air conditioning signal 71 Injector - front secondary 73 Injector - rear secondary 76 Slip lockup signal 77 Torque reduced signal
Use the codes to direct you in fixing the car. Also remember that disconnected hoses, misrouted vacuum lines, or internal engine problems can be present without causing a code.
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