I will dig that up for you. I helped LoKar get the DBW setup working that they have on the market
I will dig that up for you. I helped LoKar get the DBW setup working that they have on the market
I have information from EFI Connections, see pic below. It seems to me the Mitchel's Manual might not be in agreement with the EFI Connections schematic. The Stop Lamp In are in agreement with both Mitchel's Manual and EFI Connections schematic.
So here is what I'm thinking. Wire both the Stop Lamp In and Brake Switch like the EFI Connections schematic.
dave w
The EFI Connection schematic appears correct for Gen III (specifically early Gen III).
TCC brake circuit to PCM is a "normally closed" circuit - PCM receives 12 volts of power when brakes are NOT applied - this is used to control TC lockup.
Cruise Control brake circuit is a "normally open" circuit - PCM receives 12 volts of power when the brakes ARE applied - this is used to disengage Cruise Control (for decel or a stop).
What year, make, and model is your donor engine wiring harness from ?
Have all of the GM schematics .....
The donor vehicle was a 2000 1/2 Ton Pickup 2WD - 5.3 liter / 4L60E.Originally Posted by Buzz
I'm thinking for this conversion, 5.3 liter / TH350 the brake switch wire and stop lamp input wire are not needed?
The schematics I'm using are attached.
dave w
Wiring harnesses can range from bare bones to highly intricate - depending on the end use, desired functionality, available time, budget, etc.
Neither of those brake inputs are mandatory with a TH350 - with a couple of caveats. Without the TCC brake input wired you won't be able to a execute a CASE Learn (or CKP System Variation Learn) of the PCM - some people never bother doing this anyway. Cruise Control (if desired) is also off the table.
The brake input is a MUST for DBW at the PCM. It will go into torque management. When I say Torque Management this term covers some 400 or so parameters that cause Torque Reduction. The calibration on all 2000 calibration will try to reduce torque output if the brakes are held on. With DBW the calibration will prevent a runaway condition like the Toyota's have. email me and I will give you the schematics and other files on DBW. I work at a GM dealer from 7 to 5 every day. I have the good stuff. caleditor@pcmcalibrators.com
I participate in select automotive Forums as a means of giving back a little - as the industry has been very good to me over the years.
I try to answer questions that people have (whether or not I agree with what they are attempting).
I do not wish to enter into arguments - and will simply cease to participate if a thread heads in that direction.
My personal preference in a custom Engine Wiring Harness includes VSS, Brake, Clutch, and many other inputs. That said, some people opt to exclude these - and that is their choice. There are many vehicles (hopefully all off road) that have not been wired for Brake, Clutch, VSS, or other inputs - and will still operate (these are just a little more difficult to get running well).
The Torque Reduction linked to the TCC brake input circuit is Abuse Management - and is readily tuned out of the PCM - so no problem there.
The Toyota runaway throttle example is very important - this is meticulously monitored in GM vehicles - and significant discrepancies will cause Reduce Power Mode to occur.
Reduced Power Mode is triggered in several ways. A significant difference between the expected and actual APP sensor output will trigger REP Mode, as will a significant difference in airflow been the MAF sensor (actual) and the calculated (or expected) Speed Density airflow.
Nowhere in the diagnostic procedures I have reviewed from the GM Service Manual, does it indicate that the Cruise Control (TAC Module) brake circuit is contributory to the REP Mode diagnostic.
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