Richardsmack

Will try an extra ground. Thanks. Will post when It works or if I find a solution.

It's the 6 pin connector. E tech engine yes. e7-350. Everything was working until water came into the vecu. Replaced it with a used onne with same #'s.

Thanks Joey. Those wires I connected to 2 new temporary wires to the ecu as a test. No difference.. So I put everything back like it was. I'm thinking to buy the nexio usb link 2 with the 6 pin cable. What I saw is that the v-mac software is free Version 2.9.2. Only problem would be to get the proper config files for my vin#?

Still having the 6-4 code. Trucks is in limp mode. I went to the dealer 2.5 hr drive one way. After they installed the software on the laptop and with help from mack support (3 hours later) they were able to read the ecu and the vecu. In the ecu was a different vin# and it read e7-460.... I think they updated the vecu with this vin#. Not sure as I was not there all the time. The problem stayed the same. Even though I measured all the connections and wires they decide to do that again. No luck. 7 hours later. The mechanic was afraid to program the ecu with my own vin# because he was afraid the truck would not run anymore after the update. So now I'm really stuck.... Would it be a 460? or just the ecu from a 460? I'm almost sure it's a 350 as the truck came with that engine and it shows on the valve cover. I'm out of options. If a mack dealer can't fix stuff... It would be nice if I could send the ecu and the vecu to someone who knows what he's doing. If you have any ideas please let me know. Thanks for your help.

Checked connections and they're ok. So I think the software versions are different between the old and the new VECU. However I keeps on running when driving. Have to do some other work before the inspection and then it needs to be hooked up to a computer to verify the programming....

Pffff. Had it idling for a while then it shut itself off. Started it the after 10 min it did shut off again. Engine code bulb did not work. Now it does. Fault code 6-4 which is J-1939 link which is communication between de VECU en computer aside of the engine. So now I have to check connections again.... Man I hate electronics.

Made a MacGyver plastic cover :-)

Put in the new/used vecu from a CH with the same part#: It started right up Yeee Haaaa. Thanks everyone for your help.

Thanks :-) At least all the wiring is looked over and everything is clean now. Once I find the new/used V.E.C.U I'm going fabricate a plastic cover so that it can't happen anymore. It has been a good learning curve as well. Will let you know when the box is in and if it works. Thanks!

Well as kinda expected the unit is fried. It works a bit better though. So now I have to find the module for a reasonable price.

Day #4..... Was reading the truck manual and it pointed to a circuit electrical box behind a panel under dash passenger side. Opened the panel up and discovered the box and disconnected it. Water came out...... Drying and cleaning it now. Hopefully it still works. If not I have to look for another box. Let's hope for the best. While drying I have to see where water comes into the cab. I'm getting somewhere :-) Will let you know. Thanks !

Maybe I fried the ecu.....

Today I cleaned all the grounds. Cleaned battery terminals and connection cables. Disconnected ecu and tried the ignition no difference. Cleaned the fuses and checked them. Disconnected the alternator and tried. The power stays on if the ignition is off. When starting it turns the starter when let go of the key everything shuts off proper. I noticed that when turning the key in the on position I don't see the orange engine fault lighting up anymore. checked and changed that bulb. Anyways I'm out of options. When I take every relay out everything is out/off except for the parking brake light. When I put the relays in everything has power still with ignition off..... Time for a beer. So it keeps the power on but I cannot find another relay which might be sticking............................. I'm out of ideas.

It must be a ground problem. Again when I put the ignition on on everything goes on. When I turn the ignition off power stays on as whenever i pull a relay and put it back it clicks plus the heather blower stays on and fuel gauge and both have nothing to do with the ecu. But then when you crank the engine it starts but shuts down right away and then everything shuts off. Sorry for repeating :-) it does not make sense to me grrrr. Will post when I make progress. Thanks for the help !

Cleaned the contacts on the 50A breaker and checked with multimeter(black box). Same with the starter relay. Just in case bought a new ignition switch and connected. I can't find the acc relay. All I can find see picture. The one hanging loose in front of the fuse panel is for daylight running lights (now disconnected). The other one loose see first picture is I think acc relay which I swapped. Tomorrow when the sh... rain is gone I will clean all the grounds on the frame.