LS2 data bus and VATS questions
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From: Hudsonville, MI
LS2 data bus and VATS questions I am working on an 05 GTO LS2 swap in a 57 and am stumped on the wiring for the DLC. I have tried to connect with HP Tuners and the comm is down. the current setup is as follows:
4 - Ground
5 - Ground
6 - GMLAN -
14 - GMLAN +
16 - Batt+
Now, my conventional wisdom asks "where is the UART line?" well thats pin 9 according to the connector end view on Techline, but shows no GMLAN lines going to the DLC, while the schematic shows GMLAN lines going to the DLC on pins 6 and 14, and a UART line going to pin 9. Now, the schematic shows the UART line going from the DLC to the powertrain interface module (PIM), then GMLAN going through the TCU, EBCU, and finally the ECU. So my thought was the PIM converts UART to GMLAN and talks that way, but i look online at harnesses on Speartech etc.. and see no PIM, and only four wires going into the DLC, obviously pin 16 Vbatt, 4&5 grounds and ??? I dont know, looks like pin 6 or 14?
Anybody?
Also will the fuel pump prime if VATS has not been removed? Any other security features to worry about reprogramming in the car?
4 - Ground
5 - Ground
6 - GMLAN -
14 - GMLAN +
16 - Batt+
Now, my conventional wisdom asks "where is the UART line?" well thats pin 9 according to the connector end view on Techline, but shows no GMLAN lines going to the DLC, while the schematic shows GMLAN lines going to the DLC on pins 6 and 14, and a UART line going to pin 9. Now, the schematic shows the UART line going from the DLC to the powertrain interface module (PIM), then GMLAN going through the TCU, EBCU, and finally the ECU. So my thought was the PIM converts UART to GMLAN and talks that way, but i look online at harnesses on Speartech etc.. and see no PIM, and only four wires going into the DLC, obviously pin 16 Vbatt, 4&5 grounds and ??? I dont know, looks like pin 6 or 14?
Anybody?
Also will the fuel pump prime if VATS has not been removed? Any other security features to worry about reprogramming in the car?
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Joined: Apr 2008
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I am working on an 05 GTO LS2 swap in a 57 and am stumped on the wiring for the DLC. I have tried to connect with HP Tuners and the comm is down. the current setup is as follows:
4 - Ground
5 - Ground
6 - GMLAN -
14 - GMLAN +
16 - Batt+
Now, my conventional wisdom asks "where is the UART line?" well thats pin 9 according to the connector end view on Techline, but shows no GMLAN lines going to the DLC, while the schematic shows GMLAN lines going to the DLC on pins 6 and 14, and a UART line going to pin 9. Now, the schematic shows the UART line going from the DLC to the powertrain interface module (PIM), then GMLAN going through the TCU, EBCU, and finally the ECU. So my thought was the PIM converts UART to GMLAN and talks that way, but i look online at harnesses on Speartech etc.. and see no PIM, and only four wires going into the DLC, obviously pin 16 Vbatt, 4&5 grounds and ??? I dont know, looks like pin 6 or 14?
Anybody?
Also will the fuel pump prime if VATS has not been removed? Any other security features to worry about reprogramming in the car?
4 - Ground
5 - Ground
6 - GMLAN -
14 - GMLAN +
16 - Batt+
Now, my conventional wisdom asks "where is the UART line?" well thats pin 9 according to the connector end view on Techline, but shows no GMLAN lines going to the DLC, while the schematic shows GMLAN lines going to the DLC on pins 6 and 14, and a UART line going to pin 9. Now, the schematic shows the UART line going from the DLC to the powertrain interface module (PIM), then GMLAN going through the TCU, EBCU, and finally the ECU. So my thought was the PIM converts UART to GMLAN and talks that way, but i look online at harnesses on Speartech etc.. and see no PIM, and only four wires going into the DLC, obviously pin 16 Vbatt, 4&5 grounds and ??? I dont know, looks like pin 6 or 14?
Anybody?
Also will the fuel pump prime if VATS has not been removed? Any other security features to worry about reprogramming in the car?
If HPT sees the CAN it should connect. Maybe CAN hi/lo are swapped somewhere or continuity not good. CAN hi should go back to pin 1 on C1, CAN lo to pin 2.
What are you using for a harness? Factory?
Fuel pump will prime irrespective of VATS.
Thread Starter
11 Second Club
iTrader: (17)
Joined: Mar 2007
Posts: 756
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From: Hudsonville, MI
Yes its a factory harness. Its a friends car that I am just programming for standalone. I was thinking without a prime, MIL or communications he might not have power or ground to the ECM. I asked him to check that last night, we'll see whats happens. Thanks for the great response.
