Hey all

I have a 2001 Dakota Sport 4 wd. This is a pretty basic model, standard trans. crank windows. Lately, the 4 wheel drive will not engage or sometimes will engage and stay stuck in 4 hi. When it happens I get the service 4 wd light. Now with that said, I can turn the ignition on and off and sometimes I get the transfer case switch lights and can toggle back and forth with no issues and can hear the shift motor cycling. Other times I get absolutely no light on the switch. I was going to check the connections at the shift motor this weekend. I have read some threads on the TCCM. Would a bad one give me the sporatic conditions I mentioned above? Any other advice would be appreciated. I already checked the fuses and all checked fine.

 

Is there any other issues other than the 4wd? Such as other lights not working, the speedo not working all the time or stuff of that nature? Or is it only an issue with 4wd related components?

 

mine did the same thing my 02..i used to tap on shift motor with a snow brush and it would shift out of 4 hi, finally replaced shift motor, its either the connection on TCCM or Tccm itself possibly connection on shift motor or the motor itself, but bpark might be onto something as well, if ya do get a new or parts yard Tccm make sure to get it flashed if ya still have problems

 

Mine wouldnt go into four low, the light would just flash. Got under the truck and cleaned the connection, works everytime now. Dirty or fouled connections are always the first place to look.

 

Hi bp. Once in awhile the door ajar light stays on when clearly both doors are shut. Other than that one weird thing it is just the 4 wheel drive.

 

I checked all the connections this weekend and they were all clean and connected properly. I'm leaning toward the TCCM being the problem as ever once in awhile The switch gets the lights and the motor shifts. Is there a way to test the TCCM? I've found plenty of them used for a reasonable price but how does the salvage yard know they are good? I know it is somewhat of a gamble purchasing used electrical components.

 

OK guys....really need some help. I replaced the TCCM....still nothing. No lights on switch unless truck is running an then only the 2 wd light, no neutral light, won't switch into 4 wd. still getting the Service 4wd light. Where should I go next? Switch, shift motor/mode sensor assembly? Does the central timer have anything to do with 4 wd?

 

No, the CTM has nothing to do with 4wd.

Did you check both fuses? #11 in the junction block and fuse "A" in the PDC?

Since the switch seems intermittent check for a bad connection there.

 

Yup, checked both fuses about 10 times just to make sure. Got the switch out now, didn't seem like the connection was bad or dirty. Is there a way to check the switch. I have a service manual but doesn't really say how to check the switch. I have read that if you disconnect the battery, it can cause the system to go into default mode which will only be 2 wd. Not sure if this is an internet myth? My battery did crap out on me last winter but I didn't notice if the problem started then as we had such a mild winter that I never even tried using the 4 wd.

 

Pins 1 and 5 are the switch. It's multiplexed, two wires use different resistances for each mode. The values are not in the service manual.

You should find 5 volts on Pin 1.

The TCCM does interface with the PCI bus. A DRB can "talk" to it.