99 Ram with the 5.2 in it 2WD has always randomly gone into limp mode with code P0753 and i always just clear the codes and it runs fine. Usually only happens when i let the truck sit for awhile and then decide to drive it, once cleared it will not come back unless the truck sits again for a week or two.

Now the dreaded code will not go away and its also throwing these following codes:

P0443 (Evap system purge control valve "A" Circuit"
P0753 1-2/4-5 Solenoid Circuit
P1765 Transmission Power Relay Circuit
P0743 TCC Solenoid Circuit

These codes only came up AFTER the original p0753 code will not erase, i have checked relays and swapped good ones with bad ones and nothing has changed. I also noticed the transmission relay with the key on and engine off clicks repeatedly-say about 100 clicks in minute maybe even more. I checked my connections for corrosion on my PCM and didnt notice anything out of the ordinary, all pins looked clean. Fluid looks good, doesnt smell burnt and at the normal fill level. I am aiming towards replacing the transmission shift solenoid but want some other input before i throw parts at it. Any input is appreciated!

***I attached the video of the relay-not sure if it'll load or not

 

If the trans isn't getting power, it simply isn't going to work. Try swapping the trans relay with the horn relay. See if that doesn't clear some of the codes.

 

i did that and nothing changed. Were you able to see the video i added? Thats what the relay is doing with the key ON but engine not running. Once i run the engine the relay does not click like that anymore

 

i did that and nothing changed. Were you able to see the video i added? Thats what the relay is doing with the key ON but engine not running. Once i run the engine the relay does not click like that anymore

 

PCM should engage the relay for a few seconds at initial key on, then kill it again, until it sees the engine turning. I think.... It *may* have it on whenever the ignition is on, for that matter. If it was the latter case, that would more explain your symptoms..... Might be as simple as a bad connection on the control circuit ground, or PCM ground. Think I would start by check connections at the PCM, make sure they are clean, and tight, and that the PCM has a good ground..... See what happens.

 

im gonna go check this out now, where can i find wire diagrams for this truck? I have a hanes manual but it doesnt have a transmission wiring diagram..unless i am over seeing it.

 

Cleaned the grounds to the PCM and also any grounds going to the battery and nothing changed.

with the key on engine off that transmission relay is buzzing/clicking extremely fast really loud

 

Have a look here. Service manuals for our trucks. Wiring diagrams are in section 8W.

 

Is ther anyway to check if transmission is getting 12v without taking off the pan?

 

thanks for this