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GM BPP Circuit Signal applied 06 saab 9-7x Trailblazer Cruise No op.
Troubleshooting a cruise non operational, will not enter cruise at any speed.
older girl on a odd ball ecu, E40. In a Tech2 tech2win in cruise section everything
functions as it should other then BPP circuit signal is always applied...
No matter what happens this is always set to applied.
Brake switch is 3 single switches in one, like many from this era. NO true bpp
other then a BPP that is related to the adjustable pedal setup.
Tested the brake switch, metered out good both the switch and wires separately
tested. Looked for a BPP relearn and there is not one for this girl in tech2win for
her.
Programmed a different ecu as i read fresh programming can cause ecu to learn
on some models, did not change the status of it in the shop.
Tracing wires now to confirm correct wiring at each module and receiving power, etc..
Before slamming parts at it... yuck
ecu, trans, ebcm
WHAT module actually sets the BPP circuit signal applied ? I believe this is my issue
with the cruise not working.
After reviewing the attached diagram, the brake switch applies power at rest from IGN E Fuse 22 (pink wire into the switch, purple wire out) to the ABS module (pin6) and ECM (pin 46) identified as Cruise Release. So on these circuits, 12v means brake released, less than 12v means brake applied. (This could mean no voltage, or some bias voltage provided from the module waiting to be overridden by the switch voltage, that's why I quantified it is as "less than 12v" and not 0v, or 5v, or 3.5v etc..)The brake lamp switch also incorporates a normally open switch, which is feed power on the orange wire from the stop lamp fuse 12 25A. When the brake pedal is applied, this circuit closes and applies power through the switch to the white wire of the switch, to the Vehicle Stop Fuse 35 15A in the rear fuse block, which goes to the TCM on pin 42 light blue and ECM pin 32 light blue. On these circuits, 12v means brake applied and less than 12v means not applied.
There is zero documentation on this signal in all information i have searched and read. ONLY way i know about it as it is a PID on the tech2 otherwise nothing....
All wiring has been checked both unplugged and then plugged in to verify, everything still checks out perfectly normal.
changed ecm, changed tcm, both fresh new programming
As soon as the ecm has power this is set, no other module seems to affect this when removed from power/communication. Nothing i have done to this point has changed it from applied.
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