Here are the Part Numbers for the GM PWM Module Connector
#22
1) maybe you have a different model than the ones I've tested.
2) your temperature has never gone high enough to warrant the fans going over 90%
3) you are playing Russian thermal runaway roulette with your engine.
If it was me, I'd test it. Should be much easier than replacing the engine. Temporarily tell you engine managment to turn the fans on 100% and see what happens.
#24
I can think of three possible responses.
1) maybe you have a different model than the ones I've tested.
2) your temperature has never gone high enough to warrant the fans going over 90%
3) you are playing Russian thermal runaway roulette with your engine.
If it was me, I'd test it. Should be much easier than replacing the engine. Temporarily tell you engine managment to turn the fans on 100% and see what happens.
1) maybe you have a different model than the ones I've tested.
2) your temperature has never gone high enough to warrant the fans going over 90%
3) you are playing Russian thermal runaway roulette with your engine.
If it was me, I'd test it. Should be much easier than replacing the engine. Temporarily tell you engine managment to turn the fans on 100% and see what happens.
Where did this 90% deal come from anyway?
#25
TECH Senior Member
iTrader: (7)
Working on putting the trans back in and I will test it...however, looking at HP tuners and what I have programmed in there, it is set to go to 100% and I've never seen the temp gauge go over 200 degrees when at low speed or idling.
Where did this 90% deal come from anyway?
Where did this 90% deal come from anyway?
Andrew
Last edited by Project GatTagO; 01-11-2019 at 12:35 PM.
#26
Working on putting the trans back in and I will test it...however, looking at HP tuners and what I have programmed in there, it is set to go to 100% and I've never seen the temp gauge go over 200 degrees when at low speed or idling.
Where did this 90% deal come from anyway?
Where did this 90% deal come from anyway?
https://ls1tech.com/forums/forced-in...-less-diy.html
#27
Andrew, did you arrive to your test conclusion based on the Holley ECM system? I wonder if the GM E-38 accounts for knowing that 100% output should relate to an actual 90% duty cycle. I verified that my ECM was set up to run fans to 100% and they in fact run at high speed when engine temp is up at the maximum temp.
#28
TECH Senior Member
iTrader: (7)
Andrew, did you arrive to your test conclusion based on the Holley ECM system? I wonder if the GM E-38 accounts for knowing that 100% output should relate to an actual 90% duty cycle. I verified that my ECM was set up to run fans to 100% and they in fact run at high speed when engine temp is up at the maximum temp.
Andrew
#29
TECH Senior Member
iTrader: (7)
Here is the lat g thread...the information is buried in there somewhere.
https://lateral-g.net/forums/showthread.php?t=40215
Andrew
https://lateral-g.net/forums/showthread.php?t=40215
Andrew
#30
Got the Chrysler relay, Dorman 902-310, and looks good.
Got this definitive explanation in plain English from vw_chuck. Thanks chuck
Dude run a Dorman 902-310 SSR. It is a 40 amp solid state relay. Low side drive just like a normal relay. None of that Ford clusterfuck above.
So no internal ramp up/down. Grounding the control line turns the unit on, hittting it with a PWM ground at variable duty controls the fan/pump rate. Just a 40 amp solid state relay. Seems to take whatever duty cycle I command it. Of course the pump wont run with too low of a duty so test it out and set bounds appropriately.
Apparently there is also a 902-303 part which according to aknovaman has a different pin out. For Dorman 902-310 module with Pin 1 being the outer most large gauge wire
pin 1 - Fused +12V
pin 2 - Output to load
pin 3 - ground
pin 4 - Control wire (Megasquirt PWM to ground)
I couldn't run it straight off an Ardunio pin. Even 5V on the control line turns the relay on full. Hooked up an optoisolator and all is good. A normal ECM will ground the control wire properly, I think I was doing something wrong commanding the ardunio
Got this definitive explanation in plain English from vw_chuck. Thanks chuck
Re: A few questions about fuel pump pwm
by vw_chuck » Wed Jan 10, 2018 11:19 amDude run a Dorman 902-310 SSR. It is a 40 amp solid state relay. Low side drive just like a normal relay. None of that Ford clusterfuck above.
So no internal ramp up/down. Grounding the control line turns the unit on, hittting it with a PWM ground at variable duty controls the fan/pump rate. Just a 40 amp solid state relay. Seems to take whatever duty cycle I command it. Of course the pump wont run with too low of a duty so test it out and set bounds appropriately.
Apparently there is also a 902-303 part which according to aknovaman has a different pin out. For Dorman 902-310 module with Pin 1 being the outer most large gauge wire
pin 1 - Fused +12V
pin 2 - Output to load
pin 3 - ground
pin 4 - Control wire (Megasquirt PWM to ground)
I couldn't run it straight off an Ardunio pin. Even 5V on the control line turns the relay on full. Hooked up an optoisolator and all is good. A normal ECM will ground the control wire properly, I think I was doing something wrong commanding the ardunio