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2002 3.2v-6 rodeo front axle vacuum shift motor

8K views 13 replies 4 participants last post by  Joncarn 
#1 ·
I have a 2002 Rodeo with 3.2 V-6, 4x4 and while driving the 4x4 randomly tries to engage without pressing the 4x4 dash button. After reading several threads I decided to check the vacuum lines at the axle and I discovered that I have only 1 vacuum line on the motor, not 2 like the worthless Haynes manual shows. I finally removed the motor after locating the wiring connector, which again was nowhere close to what the pictures in the manual shows, and removed the plastic cover. This motor does not have any vacuum switches inside, it's all electric.
What is going on its this thing? Why only 1 vacuum line? How do I test the motor now to see if it's working? The wiring is 4 wires, blue, green,white and black. I'm guessing the 4x4 dash switch just changes the polarity to reverse the motor, but because my 4 wire colors don't match the wiring diagram I am not sure which wires to power for testing.
What is also strange about this is that the transfer case motor should not be working at all, one of the magnets inside the motor came unglued from the housing and it is not engaged.
Is the 2003 model year different and I possibly have an early 2003 model even though the VIN indicates 2002 model year?
 
#2 ·
The axle actuator on 2000 and newer Rodeo's is electrical as opposed to vacuum. The hose is a vent for the axle tube and has nothing to do with actuator operation.
This is the electrical schematic for the axle actuator, click on image to expand.
Chuck the Haynes in the trash.
 

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#3 ·
Thanks for the diagram. I bench tested the axle motor and it works. Fixed the magnet in the transfer motor and it works. The transfer case is engaging/disengaging when the dash button is pressed, but the axle motor is not. While I was driving it before, I could hear a lot of clicking coming from the console when the light was flashing, is the computer for this under the console or is they a relay? I see 2 controllers in the diagram so I'm thinking the problem is in one of these
 
#4 ·
The 4WD Control Unit is under the center console, the SOF Controller is shown in the image.
Shift on the Fly (SOTF) Controller ((Isuzu/Honda part # # 8-97211-143-3)
Connector C49
1__*LATCH*__2
3__4________5__6

Pin 1_Motor Control signal to Axle Actuator Pin 4**Red
Pin 2_Motor Control signal to Axle Actuator Pin 3**Green
Pin 3 _+12 Vdc when Ignition switch is in Run (On) via Fuse CB14 15 AMP Turn/Backup Lamps**White/Green
Pin 4_2WD/4WD control signal from 4WD Control Unit**Brown/Yellow
Pin 5 No Connection
Pin-6_Chassis ground**Black
 

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#5 ·
I disconnected the SOF relay but the indicator light in the dash is still blinking and I can hear the controller on the transfer case engaging and disengaging. I disconnected the electrical connector from the front axle actuator so at least it's not engaging. Do you have a part number or picture of the 4-wheel drive controller? I pulled the center console out and I have 2 boxes, one orange and one black. The black one doesn't even have a number on it, the orange one does and it also has "indicator" labeled. I also pulled the turn signal fuse and that stopped the light, but also caused the transmission selector to stop working, which really confused the ECM, causing really hard shifts between 2nd and 3rd gear. Trans shifts fine when I put the fuse back.
 
#6 ·
4WD Control Unit, (Isuzu/Honda part # 8-97165-958-0)
Connector B19
1__2__3__4__*LATCH*__5__6__7
8__9_10_11_12_____13_14_15_16

Pin-1_Transfer case Actuator Motor control signal**Yellow/Green
Pin-2_Transfer case Actuator Motor control signal**Blue/Green
Pin-3_NC
Pin-4_NC
Pin-5_2WD/4WD select switch signal, +12 Vdc via Turn/Backup fuse when Ignition Switch is in Run (On)**Blue
Pin-6_Ground level signal from Pin 2 axle actuator indicating it in the 4WD position**Brown/White
Pin-7_Ground level signal when transfer case actuator is in the 4WD engaged position**Blue/White
Pin-8_2WD/4WD control signal to SOTF controller module to operate the front axle actuator**Brown/Yellow
Pin-9_NC
Pin-10_Chassis ground**Black
Pin-11_NC
Pin-12_+12 Vdc from Turn/Backup fuse when Ignition Switch is in Run (On)**White/Green
Pin-13_Ground level signal to operate the "Wheels" icon**Blue/Red
Pin-14_4WD engaged signal to ABS electronic module (disables ABS in 4WD)**Orange
Pin-15_Ground level signal from Transfer case Actuator Switch 2WD position**Brown/Blue
Pin-16_Ground level signal from Transfer case Actuator Switch 4WD position**Brown/Red

The SOTF Controller receives a 2WD/4WD command signal from the 4WD Control Unit,
it responds by sending a DC voltage to the Axle Actuator motor causing it to rotate and
engage/disengage the left front axle locking mechanism.
 

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#9 ·
Buster28 said:
The 4WD control unit is the same on 98-99, however, it controls a Vacuum Solenoid Valve (VSV) as opposed to the 00-02 SOTF controller.
It looks like I found a good thread to post this issue. My 97 Trooper LS has me scratching my head again. Last year when trying to shift into 4WD the dash light would not come on to indicate the actuator was engaged; so, anytime I needed 4x4 I had to crawl underneath and swap the vacuum lines...which did illuminate the 4x4 dash light and engage the front axle. I just figured the age and corrosion of the VSVs were to blame for the transfer case shifter (2WD/4H/4L) not controlling the actuator and dealt with it.

Well...After a recent trip to my local pull-n-pay (who miraculously had a lesser corroded Trooper), I pulled the VSVs and actuator from the front axle. I know my actuator works fine but pulled the whole thing since the cost was the same. Last weekend I installed the 'new' VSVs and spliced-in the wire harnesses believing this would cure my aging Trooper...but sadly, this was not the case. I tried the SOTF and there was no dash light indicator or actuator engagement. :roll:

I know the vacuum lines are good. I know the actuator is good. I know the actuator switch that illuminates the 4x4 dashlight is good. I'm fairly confident the VSVs are good. What could be the most likely reason why the VSVs are not receiving the signal to switch them open and closed? Where in the SOTF system is the electrical connection made when I take the shifter out of 2WD and move it into 4H? Is there an internal transfer case switch? Is there a solenoid located somewhere under the hood? Is it the 4WD control unit? I'm a little stumped and I'm calling out for help. Many thanks in advance.
 
#10 ·
I don't know how similar the Trooper transfer case is to the rodeo, but you may want to check the motor on the transfer case. One of the magnets for that motor had come unglued from the housing and it prevented the transfer case from engaging. Mine was partially turning so you can't just listen from underneath, you need to take the motor apart.
 
#11 ·
Joncarn said:
I don't know how similar the Trooper transfer case is to the rodeo, but you may want to check the motor on the transfer case. One of the magnets for that motor had come unglued from the housing and it prevented the transfer case from engaging. Mine was partially turning so you can't just listen from underneath, you need to take the motor apart.
:? Thanks, but I'm not looking for an "I don't know how similar" type answer...especially since my transfer case engages just fine. I'll just stop now. Please, only chime in if you actually read and fully comprehend the issue.
 
#13 ·
Joncarn said:
sorry to bother you
Relax Joncarn...you're not bothering me; I apologize if you thought this was the case. I appreciate your tidbit of info and suggestion, but it simply does not apply to the electrical portion of the SOTF system that is puzzling me at the moment. After reading my reply I can see where I might have come across as a bit of a d!ck :oops: , so again...I apologize.

I was kinda hoping Buster28 (the 4L30E guru) might offer up a suggestion since he seems completely knowledgeable and full of suggestions, wiring diagrams, photos, etc.

I did read a post regarding a 2000 Rodeo 4x4 engagement issue, and one picture showed a 4WD Transfer Switch located in the center console next to the transfer shifter. I don't know if my 97 Trooper is set up the same but if I get time to pull the console out then I might start there. Any thoughts or suggestions are appreciated.
 
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