bart_r6
Junior Member
Hey Guys,
Really need some help here trying to figure out my 4x4 issue. I have a 2018 ram 1500 and a few weeks ago a "service 4x4" message came up on my cluster and ever since then I'm not able to shift into 4x4. I have read and searched a lot of posts trying to figure this out but I'm stuck and dont know where to go from here. During the last few weeks I have done and found the following:
1. Because of C1464 and C147B all the posts I have read said to replace the front axle lock actuator. I took one off my other ram and swapped them and still nothing. I cleared the codes and they came back right away withing 2-3 seconds of clearing them. I know my actuator is good because it worked fine in the other truck. When I try to select 4 lock or 4 low nothing happens and the led light does not illuminate next to those 2 buttons.
2. I checked the plug connector and it also appears to be good and all 4 wires are in good shape.
3. I checked the voltage at the plug while it was disconnected from the FAD and I get 11.2V at pin 3 and 4.05V at pin 2. The ground at pin 1 was also checked and is good. Just for reference the voltage at the battery was 12.4V while checking the output at the plug. After checking the voltages with a voltmeter I also used a test light as was suggested in one of the posts I read but it did not illuminate at all even tho I was getting 11.2V with the voltmeter. I think this might be an issue but dont know what to check next.
4. Checked fuse 77 which was good as well as I took out the entire fuse box and inspected the wire harness connector plug which was located underneath and everything looked good there....no corrosion or broken wires at the connector.
5. One thing that I found while trying to trouble shoot this whole thing over the last few weeks is that currently the truck is stuck in 2WD. When I go under the truck the shaft between the front diff and transfer case is free and i can turn it by hand. In this situation when I scan the DCM for codes I only get the 1 code C1464. Now when i go and clear the code I have 2-3 seconds when the service 4x4 message dissappears from my cluster and during that short time if I hit the 4x4 lock button the transfer case will actually allow the truck to shift into 4x4. When i try to move the shaft connecting the transfer case and front diff now its solid and I cant turn it by had anymore. So now the cluster has the 4x4 symbol illuminated on the right side plus the 4x4 lock led light is light up on the button and when I read the codes now I get the C147B code. The original code C1464 is gone in 4x4 mode. As soon as i go to clear the code ...same thing happens ...I get 2-3 seconds before the service 4x4 message comes right back up on the screen and i'm unable to select 2wd or 4low. The only way to go back into 2WD is to clear the C147B code and while I have that 2-3 seconds when the scanner is clearing the code i can press 2WD button and truck will shift and go into 2WD. At this point i'm locked out again from shifting into 4x4 and we get the original code of C1464 while scanning when 2WD is selected.
Sorry for the long write up but i wanted to provide as much info as possible for someone here to point me in the right direction what to do next. In 2 weeks I'm going way up north for a snowmobile trip where having a functioning 4x4 truck is essential so I need to figure this out asap please. Going to the dealer is not an option as the truck is out of warranty because of the milage. Any and all help would be greatly appreciated.
Really need some help here trying to figure out my 4x4 issue. I have a 2018 ram 1500 and a few weeks ago a "service 4x4" message came up on my cluster and ever since then I'm not able to shift into 4x4. I have read and searched a lot of posts trying to figure this out but I'm stuck and dont know where to go from here. During the last few weeks I have done and found the following:
1. Because of C1464 and C147B all the posts I have read said to replace the front axle lock actuator. I took one off my other ram and swapped them and still nothing. I cleared the codes and they came back right away withing 2-3 seconds of clearing them. I know my actuator is good because it worked fine in the other truck. When I try to select 4 lock or 4 low nothing happens and the led light does not illuminate next to those 2 buttons.
2. I checked the plug connector and it also appears to be good and all 4 wires are in good shape.
3. I checked the voltage at the plug while it was disconnected from the FAD and I get 11.2V at pin 3 and 4.05V at pin 2. The ground at pin 1 was also checked and is good. Just for reference the voltage at the battery was 12.4V while checking the output at the plug. After checking the voltages with a voltmeter I also used a test light as was suggested in one of the posts I read but it did not illuminate at all even tho I was getting 11.2V with the voltmeter. I think this might be an issue but dont know what to check next.
4. Checked fuse 77 which was good as well as I took out the entire fuse box and inspected the wire harness connector plug which was located underneath and everything looked good there....no corrosion or broken wires at the connector.
5. One thing that I found while trying to trouble shoot this whole thing over the last few weeks is that currently the truck is stuck in 2WD. When I go under the truck the shaft between the front diff and transfer case is free and i can turn it by hand. In this situation when I scan the DCM for codes I only get the 1 code C1464. Now when i go and clear the code I have 2-3 seconds when the service 4x4 message dissappears from my cluster and during that short time if I hit the 4x4 lock button the transfer case will actually allow the truck to shift into 4x4. When i try to move the shaft connecting the transfer case and front diff now its solid and I cant turn it by had anymore. So now the cluster has the 4x4 symbol illuminated on the right side plus the 4x4 lock led light is light up on the button and when I read the codes now I get the C147B code. The original code C1464 is gone in 4x4 mode. As soon as i go to clear the code ...same thing happens ...I get 2-3 seconds before the service 4x4 message comes right back up on the screen and i'm unable to select 2wd or 4low. The only way to go back into 2WD is to clear the C147B code and while I have that 2-3 seconds when the scanner is clearing the code i can press 2WD button and truck will shift and go into 2WD. At this point i'm locked out again from shifting into 4x4 and we get the original code of C1464 while scanning when 2WD is selected.
Sorry for the long write up but i wanted to provide as much info as possible for someone here to point me in the right direction what to do next. In 2 weeks I'm going way up north for a snowmobile trip where having a functioning 4x4 truck is essential so I need to figure this out asap please. Going to the dealer is not an option as the truck is out of warranty because of the milage. Any and all help would be greatly appreciated.