Communication Error
It is possible to receive a communication error from a IDS or equivalent tester when initiating a diagnostic test or accessing PIDs. The communication error can be caused by operator error, the vehicle wiring, connectors, the PCM or other control modules connected to the DLC wiring. The PCM will respond to a IDS or equivalent tester whenever the tool requests a test. These are not DTCs. Listed below are numeric codes and generic descriptions that a scan tool may display when trying to carry out some PCM operations. It is possible to get other numeric codes not listed. For a complete list of communication response codes, see society of automotive engineers (SAE) document J2190 enhanced E/E Diagnostic Test Modes. Some are normal responses to valid requests. The others are communication error responses. If the tool displays any of the communication error responses check scan tool connections, cable/adapters and entry of vehicle information.
| Numeric Code | Generic Description | Expanded Description |
|---|---|---|
| NORMAL PCM RESPONSES | ||
| 00 | General affirmative | PCM received a valid request from scan tool. |
| 62 | Normal exit without test results | PCM carried out a valid request from scan tool and has no results (i.e., KOEO self-test carried out with no DTCs recorded). |
| 61 | Normal exit with test results | PCM carried out a valid request from scan tool and has results (i.e., KOEO self-test was carried out and a DTC was recorded). |
| ABNORMAL PCM RESPONSES | ||
| 10 | General reject | PCM will not respond to request. |
| 11 | Mode not supported | PCM is not capable of carrying out a requested test (i.e., turn injectors on and off). |
| 12 | Invalid data format | An unrecognized character is inserted into a string of data. |
| 21 | PCM is busy at time of request | PCM is already carrying out a test at the time another test is requested. |
| 22 | Entry conditions not correct | Usually operator error (i.e., engine not running or in gear when requesting KOER self-test). |
| 23 | Asked for results before done | A message was received by the PCM but the PCM is not ready to respond. |
| 50 | Upload not accepted | A request for information or a test cannot be accomplished due to a fault condition. |
| 63 | Abnormal exit with results | While PCM is carrying out a test, an error occurred, but PCM has results (i.e., DTCs). |
| 64 | Abnormal exit without results | While PCM is carrying out a test, an error occurred and no results are available (i.e., aborted KOER self-test before DTC was recorded). |