Service 4WD Switch

[rleemann]

For those who own a first generation Grand Cherokee equipped with a VIC (Vehicle Information Center) and are aggravated with the error message and buzzer telling you to Service 4WD Switch – here is a way to stop your aggravation. After you have replaced the 4WD Switch on T-Case about $35 and the VIC continues to warn you to Service 4WD Switch.

The technical shop manual is full of tests to run on the VIC that all ultimately wind up telling to replace the VIC, an over $200 part from the stealers. Do what I did, just cover up the buzzer with a few of those small round razor cut bandages to cover up the noise.

The buzzer is located inside the BCM (Body Control Module) inside the diver side dashboard. First start by removing the two clam shell shaped plastic parts around the steering column ignition and signal control switches.

Next carefully pop off the two plastic wood grain trim pieces to expose screws you will have to remove. Start removing screws that hold on the diver side kick panel located from the far left, under the steering column, to a little piece that pops out just above the VIC. Be careful, the end piece is very fragile, pop it free before fully removing all the supporting screws of the kick panel.

Once exposed, on left of steering column remove screws supporting the headlight switch and remove it leaving it still connected, just move it to the side because you will need access through that hole to unplug and plug the BCM back in. The BCM is located just behind the metal part right under the headlight switch. Once the 3 wire plugs are removed from the BCM, unscrew the 4 screws through metal part that holds the BCM on and remove it. Pull it out through space between wiring junction to left and steering column to right.

Once BCM is out remove the 4 T15 torque screws that hold the BCM together to expose the inside and notice a round buzzer on IC board with a hole in the center of it. Place a few (3) round band-aids over the hole to prevent sound. Once hole is covered, reassemble the BCM’s torque screws. You will still get some sound from buzzer when key is left in ignition, lights left on or seat belts because those warnings are much louder than warnings from the VIC.

When reinstalling BCM, I found it easier to slip it back into position and mount one screw loosely. Next very carefully plug the three wire plugs back into the BCM starting with the two in the back of the BCM noticing the white or black plug. Remember before you put the BCM into position, which plug takes the white and which one takes the black plug. Plug in bottom 3rd wire last.

Be extremely careful not to bend one of those pins as I did, which cost me having to take it all apart again to fix the bent pin. After you put the 3 wires to BCM on and before you reassemble the dashboard, test you didn’t screw up one of the pins. Try and start the car, all warning lights should light momentarily and gages should work. If your gages don’t work, power windows don’t work then you probably bent a pin. If you bent a pin, dissemble and correct your bent pin problem.

Once you pass the smoke test (only kidding) reassemble the kick panel, pop on trim and put the clam shell things on steering column. The VIC warnings are very faint 2 sets of 3 beeps anyway, so by covering up the buzzer you shouldn’t hear anymore the warning from VIC about Service 4WD Switch as well as the other 6 audio warnings from the VIC.

Although, all warnings from VIC will still be visually displayed on VIC itself at least you stopped the damn 2 sets of 3 beeps audio warning from VIC that constantly come up about Service 4WD Switch. And, besides the VIC warning sound is so faint anyway with windows up A/C on and stereo blasting you can't hear the fact you left you turn signal on for the last mile or your down to your last gallon of gas because you only get one audio warning from those errors. I don't understand why when they designed the VIC to continually buzz you about the 4WD Switch but only buzz you once about the turn signal left on or your about to run out of gas dummy. With this I call it a band-aid fix that works.

[xj31]

It would be a lot easier to just replace the switch on the t-case that usually causes the problem.its $36.00 if you pay full list.I would rather pay that and spend 5 minutes changing it instead of wasting an hour and risking damaging the bcm.plus if its a 93-95 it doesnt even have a bcm so your fix wouldnt help on one of those

[rleemann]

Originally Posted by xj31

It would be a lot easier to just replace the switch on the t-case that usually causes the problem.its $36.00 if you pay full list.I would rather pay that and spend 5 minutes changing it instead of wasting an hour and risking damaging the bcm.plus if its a 93-95 it doesnt even have a bcm so your fix wouldnt help on one of those

Of course I replaced the 4WD Switch on the T-Case first and the VIC warning still would not go away. My GC is a 1996 and I believe the 93-95 model years don't have a VIC but as you claim they don't have a BCM either but I am sure those model years are experiencing the warning buzzer problem with the 4WD switch so the buzzer must be somewhere up under the dashboard. Only the 96-98 models affected would follow my procedure and besides the thread was addressed to only GC owners experiencing the Service 4WD Switch problem, so I only suggested a way to shut the damn warning up on a 96-98. In any case go ahead and spend the 2 to 3 hours troubleshooting and $215 for the part it ultimately will need which is a new VIC.

[mteub]

its beginning to drive me crazy especially the fact that there is nothing about it in the owner's manual or the Hanes book i picked up.

does the switch go by a different name or somehting?, becasue i can find no info on it in the hanes book i bought?

[rleemann]

Originally Posted by mteub

its beginning to drive me crazy especially the fact that there is nothing about it in the owner's manual or the Hanes book i picked up.

does the switch go by a different name or somehting?, becasue i can find no info on it in the hanes book i bought?

The switch is located on the top driver's side back of the transfer case. Part number from the stealers is 56006755 and cost $33.34 as of 7/30/04 and is called on their computer a SWITCH-TRA that is for a 96' 5.2 V8 Quadra Drive. If you change it out be sure to clean the 2 pin terminals for good contact. If that doesn't stop it like me, the VIC is bad not worth the $400 dollars to have it changed so just follow my procedure to shut the buzzer up from VIC errors.

[xj31]

I apologize,I missed the part where you said you replaced the switch.I have been working on jeeps for a long time and honestly,I have never had to replace the vic for that problem.It usually ends up to be either the switch ,connection or a wiring problem.Your situation is obviously different.I just dont like the idea of taking the bcm apart,because if you damage it,you can end up with a lot more problems for example it can keep the car from starting if you have the factory security system.

[rleemann]

Originally Posted by xj31

I apologize,I missed the part where you said you replaced the switch.I have been working on jeeps for a long time and honestly,I have never had to replace the vic for that problem.It usually ends up to be either the switch ,connection or a wiring problem.Your situation is obviously different.I just dont like the idea of taking the bcm apart,because if you damage it,you can end up with a lot more problems for example it can keep the car from starting if you have the factory security system.

Apology accepted, you mention you work on jeeps - I have seen other threads of many different jeep owners having the same problem I was having with the VIC telling me to Service 4WD Switch. And this was after I had even changed the switch, what else is there to do to service it? It wouldn’t be such a big deal but the VIC will send the error message to the BCM to issue the buzzer signal 2 sets of 3 beeps a dozen times in 3 to 5 minutes. The error message originates from the PCM or (Powertrain Control Module) coming off the sensor 4WD switch on the Transverse Case. It was driving me nuts when things like your low on gas or your turn signal was left on over a mile, it would buzz you only once. I even went so far as the buy from Chrysler for $25.02 Jeep’s Grand Cherokee 96-98 Body Diagnostic Procedures manual to try and figure out what was going on. In each test procedure of the error Service 4WD Switch the manual tells you ultimately to replace the VIC a $215 part. So I just cut to the chase to shut the hell up the buzzer by putting the round band-aids on it. Your right, you have too be careful because the first time I reassembled the BCM I bent a pin and although the car did start, the power windows didn’t, the AC didn’t and all the gages wouldn’t work also have the factory security system. After correcting the bent pin problem everything is find and love it now that I can’t hear that damn VIC’s 2 sets of 3 beeps anymore thank god. Quick question, on the 93-95 you mention they don’t have a BCM although I have heard someone with a 95 having the Service 4WD Switch problem with multiple buzzer warnings, so is that buzzer separate under the dash and I assume they have VIC’s? I read somewhere on those model years all you do is go under diver side dash board and disconnect the buzzer. Note: The Service 4WD Switch error still comes up on my VIC so that problem isn't fixed just the audible warning buzzer notice was in a sense put a band-aid on to shut it up.