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Output Codes

  1. Control unit circuitry allows checking of certain components by generating specific output signals. During output diagnosis, components can be checked by listening for their operation. Diagnostic output code will flash during testing, indicating which step control unit is in.
  2. Turn ignition switch off to erase fault memory. Turn ignition on. DO NOT  crank or start engine. If this is done, system will automatically switch to input testing when diagnostic procedure has been activated.
  3. To activate diagnostic procedure, locate 2 diagnostic connectors in drivers footwell area. Connect a test light between connectors A and B. See Figure .
  4. Connect a jumper wire to other terminal in connector A. Touch other end of jumper wire to the only terminal in connector B for at least 4 seconds.
  5. This will activate the first of 5 output steps. To proceed to the next step, touch end of jumper wire to the only terminal in connector B for at least 4 seconds. See Figure .
  6. First step (Code 4433) will activate fuel pump. Pump will continute to activate throughout all 5 steps and until diagnostic procedure is ended by turning off ignition.
  7. Second step (Code 4441) will operate OXS frequency valve at 50 percent duty cycle until next step is activated.
  8. Third step (Code 4442) will cause wastegate frequency valve to switch on and off until next step is activated.
  9. Fourth step (Code 4443) will cause cold start valve to switch on and off for about 10 seconds.
  10. Fifth step (Code 4343) causes carbon canister shut-off valve to switch on and off until step is terminated by turning ignition switch off. If necessary, output tests may be continued by repeating steps 3) through 10).
  11. If any device does not operate as indicated during output tests, see appropriate test in the SYSTEM/COMPONENT TESTS article.
CIS DIGITAL CONTROL INPUT FAULT CODE IDENTIFICATION CHART

Code System Affected Probable Cause
1111 Control Unit Defective Memory Circuits
2111 Speed Sensor Control Unit Not Receiving Signal
2112 Reference Sensor (1) Control Unit Not Receiving Signal
2113 Hall Sender (2) Control Unit Not Receiving Signal
2221 Control Unit Pressure Sensor Vacuum Hose Leak/Plugged
2222 Control Unit Pressure Sensor Defective Pressure Sensor
2141 Knock Regulation (3) Engine Or Ignition Knock
2142 Knock Sensor Defective Sensor Or Sensor Wiring
2123 Full Throttle Switch Faulty Switch Or Wiring Problem
2121 Idle Switch Faulty Switch Or Wiring Problem
2312 Coolant Temp. Sensor Sensor Or Sensor Wiring Defective
2322 Intake Air Temp. Sensor Sensor Or Wiring Defective
2342 Oxygen Sensor Sensor Or Sensor Wiring Defective
4444 No Faults Have Been Recorded N/A
0000 End Of Diagnosis (4) *
(1) Another cause could be a misadjusted distributor.
(2) Another cause could be signal is out of phase (misadjusted distributor).
(3) This would cause ignition timing to be retarded the maximum amount (7.8 degrees).
(4) This code is indicated by the light staying off for approximately 15 seconds after the start signal.
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