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LH Lead-Foot · 02-06-2018, 04:29 PM

DBW engines from 03 up use the 128K A/C VSS signal input. TAC module becomes cruise control from PCM via UART serial data. Two wire input to PCM on C1, cavity 21, VSS Low Circuit #821 (PPL/WHT). C1, Cavity 20 VSS High, Circuit #822 (LT GRN/BKL). Twist 9 time per foot to help reduce mutual induction. PCM VSS signal can be programmed to fit your speedo as VSS signal leaves PCM C2, cavity 10 (WHT) to speedo. Check your schematic and speedo requirements. TAC module uses B+ signal inputs for Cruise operation w/Drive-By-Wire (RPO Code-JK4) Just trying to be helpful.

02-06-2018, 04:29 PM	#38
LH Lead-Foot Registered User Join Date: Jan 2018 Location: Omaha, NE. Posts: 214	Re: GM Pulse Generator for electroc speedo DBW engines from 03 up use the 128K A/C VSS signal input. TAC module becomes cruise control from PCM via UART serial data. Two wire input to PCM on C1, cavity 21, VSS Low Circuit #821 (PPL/WHT). C1, Cavity 20 VSS High, Circuit #822 (LT GRN/BKL). Twist 9 time per foot to help reduce mutual induction. PCM VSS signal can be programmed to fit your speedo as VSS signal leaves PCM C2, cavity 10 (WHT) to speedo. Check your schematic and speedo requirements. TAC module uses B+ signal inputs for Cruise operation w/Drive-By-Wire (RPO Code-JK4) Just trying to be helpful.