Retrieving Diagnostic Trouble Codes (DTCS)

1999 Chevrolet Camaro Base, 2D Convertible, AutomaticSECTION Retrieving Diagnostic Trouble Codes (DTCS)
NOTE: DTCs 41-45 will only set while in BCM diagnostic mode and a button on remote keyless entry system transmitter is pressed. Codes are used to determine performance of remote keyless entry system transmitter and receiver in BCM.
  1. Turn ignition switch to RUN position to disarm theft deterrent system (if equipped). Turn ignition switch to OFF position. Remove RADIO fuse No. 17 (15-amp) from instrument panel fuse block.
  2. Turn ignition switch to ACC position. Chime will sound 1-2 times to verify system has enter programming mode for customizing special features. Within 5 seconds, turn ignition switch to OFF position, then back to ACC position. Chime will sound 3 times to verify diagnostic mode has now been entered.
  3. BCM will begin to flash codes on SECURITY indicator 4 seconds after entering diagnostic mode. Each flash of indicator represents a number (i.e., one flash followed by 2 quick flashes represents DTC 12). DTC 12 will always be the first code displayed, indicating diagnostic mode is at beginning of code display. Last code to be displayed will be DTC 55 followed by hardware configuration, then software configuration. Each code is displayed 3 times before next code is displayed.
  4. If more than one code is present, codes will display beginning with lowest current code to highest current code, followed by lowest history code to highest history code. Remote keyless entry system transmitter DTCs 41-45 will then be displayed if invoked while in diagnostic mode. Codes will cycle sequentially until diagnostic mode is exited.
BCM DTC DEFINITIONS

DTC Description
12  Diagnostic System Check
21/31  Courtesy Lights Feed Circuit Shorted To Ground
22/32  Courtesy Lights Return Circuit Shorted To Battery
23/33  Retained Accessory Power Circuit Shorted To Ground Or Battery
24/34  Fasten Seat Belt Indicator Circuit Shorted To Ground Or Battery
25/35  Security LED Present (With Theft Deterrent Only)
41 (1) Last Transmitter Message Received Valid
42 (1) Last Transmitter Message Received Had Invalid ID
43 (1) Last Transmitter Message Received Had Sumcheck Error
44 (1) Last Transmitter Message Received Had Encryption Error
45 (1) Receiver Processing Currently In 20-Second Lock-Out
55  Begin Configuration Display
(1) This is a remote keyless entry system code only. Codes are automatically cleared after they are displayed. To display codes again, a transmitter button must be pushed again.
RENDER: 1.0x

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