Powertrain Chart 6 - Multiple Pcm Codes
Some powertrain components share common feeds and returns. Certain failures of these circuits will cause multiple codes to set. Flow chart indicates groups of codes set by failure of common feeds and/or returns. If all codes in a group are set, perform diagnosis listed in that box. If all codes in a group are not set, diagnose lowest code number first.
NOTE:
Test numbers refer to numbers on diagnostic chart.
- Circuit No. 474 is 5-volt feed from PCM to MAP and TP sensors. An open or short to ground in circuit No. 474 between PCM terminal 1C14 and circuit S215 will cause Codes P022 and P032 to set.
- Circuit No. 476 is sensor return to PCM from IAT and MAP sensors. An open in circuit No. 476 between circuit S216 and PCM terminal 2A5 will cause Codes P031 and P038 to set.
- Circuit No. 1076 is sensor return to PCM from ECT and TP sensors. An open in circuit No. 1076 between circuit S217 and PCM will cause Codes P015 and P021 to set.
- Circuit No. 750 is battery feed, from engine compartment fuse block fuse D1 to TCC brake switch, which feeds TCC through circuit No. 420. An open in circuit No. 420 or 750, or an open in TCC brake switch, will set Code P039 or P090.