Pacbrake install

[hutch]

Got pacbrake installed on 2001 6 sp. and started truck and it didn't work. Everything looked OK but the relay. The company didn't know what voltage is on pin 20 of ECM. The brake works manually jumping the red and yellow in the relay base. My question is how does the ECM turn it on and off? Any suggestion welcome.

 

[hutch]

Its in and working Oo. The voltage on pin 20 is 12 volts. Taking it out for a good test drive tomorrow. Now I got three gauges to install. Lessons learned makes it all worthwhile.