Question about 2003 GMC Sonoma Extended Cab

1 Answer

No response from electronic transfer case

The 2WD button is lit; all 3 buttons light when the key is first turned on; I have checked both fuses - under hood and kick panel. I assume there is a relay somewhere. Where is it and is this likely the problem?

Posted by on

  • indian4rider Dec 05, 2008

    Where is the actuator motor?

  • frongione Dec 09, 2008

    My 2003 Sonoma won't go into 4 wheel high. What can be the problem?

×

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Top Expert:

    An expert who has finished #1 on the weekly Top 10 Fixya Experts Leaderboard.

    Superstar:

    An expert that got 20 achievements.

    All-Star:

    An expert that got 10 achievements.

  • GMC Master
  • 61,168 Answers

The most likely problem is a stuck transfer case actuator motor.

Posted on Dec 05, 2008

  • yadayada
    yadayada Dec 05, 2008

    On the transfer case

×

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

2 Answers

Got. A 2003 f150 4x4 got problems with 4 wheel drive locking in and stay in drive shaft turning front wheels not


Operationally vacuum shifts the front axle between 2WD and 4WD mode. The GEM ( Generic Electronics Module ) applies ground to the solenoid needed for the mode selected on the switch ( for ESOF ) or when the transfer case shift lever is moved ( MSOF ).The contact plates in the transfer case signal the GEM that the transfer case is engaged, and the Vacuum solenoids need to be activated ( either 2WD to 4WD or 4WD to 2WD ).

Lift and support the front of the truck so the front wheels are off the ground ( take safety precautions, chock wheels, jack stands, etc )
Key on, engage 4x4 and try to turn the front drive shaft.
- If it turns it is a problem with the transfer case.
- If it doesn't it is a front axle engagement problem ( this is what you seem to have, the transfer case is engaged and will drive the front shaft mine was a key on engine off test ).

- If the front drive shaft does not turn :
•With the truck running ( with front wheel back on the ground ), switch from 2WD to 4WD and back again, the vacuum shift motor should move the lever on the front axle.
sscullys_185.jpg
-- If the vacuum shift motor does not move:
1.Check for vacuum on the lines while shifting between modes. Pink vacuum line is 2WD mode, Light Blue vacuum line is 4WD.
2.Check the fuses for the 4WD system and the solenoids.
3.Check the vacuum lines from the vacuum shift motor to the solenoids on the firewall.
sscullys_187.jpg
4.Check the vacuum lines from the solenoids to the vacuum reservoir box behind the battery.
5.Check the vacuum reservoir box for cracks.
6.Typical solution is the vacuum lines ( to the solenoids or to the vacuum shift motor ) are cracked or the vacuum shift motor has a cracked diaphragm and has water in it.
7.Could be the shift plate contacts in the transfer case are corroded / not making good contact, and not activating the solenoids.
sscullys_186.jpg

Usually the case is cracked vacuum lines from the solenoids, the next common is a cracked vacuum reservoir box, and 1 time I have seen the mount for the vacuum disconnect motor broken ( motor floating free so it could not push against the axle )
sscullys_188.jpg

Aug 28, 2011 | 2003 Ford F150 Regular Cab

1 Answer

I can not get power to the motor to engage my front axle on my 4x4.


Power as in 12 V DC ? if yes, you are not in the correct area, the front axle is locked in and out of 4x4 mode with vacuum.

Operationally vacuum shifts the front axle between 2WD and 4WD mode. The GEM ( Generic Electronics Module ) applies ground to the solenoid needed for the mode selected on the switch ( for ESOF ) or when the transfer case shift lever is moved ( MSOF ).The contact plates in the transfer case signal the GEM that the transfer case is engaged, and the Vacuum solenoids need to be activated ( either 2WD to 4WD or 4WD to 2WD ).


Lift and support the front of the truck so the front wheels are off the ground ( take safety precautions, chock wheels, jack stands, etc )
Key on, engage 4x4 and try to turn the front drive shaft.
- If it turns it is a problem with the transfer case.
- If it doesn't it is a front axle engagement problem.

- If the front drive shaft does not turn :
•With the truck running ( with front wheel back on the ground ), switch from 2WD to 4WD and back again, the vacuum shift motor should move the lever on the front axle.
sscullys_200.jpg
Item #10 in this diagram
sscullys_10.gif
-- If the vacuum shift motor does not move:
1.Check for vacuum on the lines while shifting between modes. Pink vacuum line is 2WD mode, Light Blue vacuum line is 4WD.
2.Check the fuses for the 4WD system and the solenoids.
3.Check the vacuum lines from the vacuum shift motor to the solenoids on the firewall.
4.Check the vacuum lines from the solenoids to the vacuum reservoir box behind the battery.
5.Check the vacuum reservoir box for cracks.
6.Typical solution is the vacuum lines ( to the solenoids or to the vacuum shift motor ) are cracked or the vacuum shift motor has a cracked diaphragm and has water in it.
7.Could be the shift plate contacts in the transfer case are corroded / not making good contact, and not activating the solenoids.
sscullys_199.jpg

- If the front drive shaft turns:
For ESOF system
-- Check the fuses for the transfer case, engine compartment fuse panel, 17 & Cab fuse panel fuses 13 and 23 ( verify with owners manual, 97-97 & 99-03 MY can be slightly different on some items ).
-- Try hitting the transfer case with a dead blow hammer ( do not use a metal hammer, it can damage the transfer case ) to see if the transfer case shift motor is hung up .
-- Check the transfer case connector, to make sure the connector pins are clean and making good contact.
For MSOF systems
-- Check that the shift linkage on the transfer case is moving when the lever is moved from 2W to 4H and 4L.

Jul 30, 2011 | 2000 Ford F150 Flareside SuperCab

1 Answer

4x4 not working


Not too sure if you have a New Body Style 2004 or a 2004 heritage ( same as the 99-03 body style ) :
Here is both sets of checks for either option

**** 2004-2008 ****

Operationally vacuum holds the IWE ( Integrated Wheel Ends ) out, and once vacuum is removed the spring engages the IWE.

Lift and support the front of the truck so the front wheels are off the ground ( take safety precautions, chock wheels, jack stands, etc )
Key on, engage 4x4 and try to turn the front drive shaft.
- If it turns it is a problem with the transfer case.
- If it doesn't it is a front axle engagement problem.

- If the front drive shaft does not turn :
1.Shut of the truck ( still jacked up, and supported ) remove the vacuum lines from the IWE. The spring should push the gears in, without the vacuum line on.
2.Check the vent line ( tube that is routed into the engine compartment with nothing attached to it ), for blockages.
3.If the vent line is clear, and with the vacuum lines off the IWE should be engaged ( both front wheels locked ).
4.If they lock, the problem is with the IWE solenoid not shutting off vacuum to the IWEs. There is a TSB on the 2004-2006 IWE solenoids, a newer revision has been made, and used from 2007 and newer MYs.

- If the front drive shaft turns:
1.Check the fuses for the 4WD system ( If ESOF system ) . These are #11, #29, #30 and #111. Use a meter to check the fuses while plugged in, there are pins on the back of the fuse for this. Use a known good ground and check each side of the fuse with the other meter probe, with the meter set to V-DC ( check the scale if a setting that it will read at least 13 V DC ).
2.With the key on, if the ESOF system have someone turn the mode selector from 2WD to 4WD while hitting the transfer case with a dead blow hammer ( do not use a metal hammer, it can damage the transfer case ). Some times the shift motor will get stuck ( lack of use ? ) and the dead blown hammer will free it up.
3.There are 2 relays ( in the small engine compartment fuse / relay panel - ESOF only ) for the 4WD system, one is the CW ( **** Wise ) one is the CCW ( Counter Clock Wise ). These are full size relays, that can be bench tested, or a quick remove and replace test with the high beam relay in the cab fuse panel ( Relays R03 ). 1 at a time, remove the CW & CCW relays and install them in the position for the high beam relay, and test the high beams by pulling back on the MFS ( MultiFunction Switch ). If the high beams work with both relays, the CW & CCW relays are not the issue ).
4.Check the connector on the transfer case for the shift motor, to make sure it is not corroded.


**** 1997 - 2003 ****

Operationally vacuum shifts the front axle between 2WD and 4WD mode. The GEM ( Generic Electronics Module ) applies ground to the solenoid needed for the mode selected on the switch ( for ESOF ) or when the transfer case shift lever is moved ( MSOF ).The contact plates in the transfer case signal the GEM that the transfer case is engaged, and the Vacuum solenoids need to be activated ( either 2WD to 4WD or 4WD to 2WD ).


Lift and support the front of the truck so the front wheels are off the ground ( take safety precautions, chock wheels, jack stands, etc )
Key on, engage 4x4 and try to turn the front drive shaft.
- If it turns it is a problem with the transfer case.
- If it doesn't it is a front axle engagement problem.

- If the front drive shaft does not turn :
•With the truck running ( with front wheel back on the ground ), switch from 2WD to 4WD and back again, the vacuum shift motor should move the lever on the front axle.
{ picture of shift motor }
-- If the vacuum shift motor does not move:
1.Check for vacuum on the lines while shifting between modes. Pink vacuum line is 2WD mode, Light Blue vacuum line is 4WD.
2.Check the fuses for the 4WD system and the solenoids.
3.Check the vacuum lines from the vacuum shift motor to the solenoids on the firewall.
4.Check the vacuum lines from the solenoids to the vacuum reservoir box behind the battery.
5.Check the vacuum reservoir box for cracks.
6.Typical solution is the vacuum lines ( to the solenoids or to the vacuum shift motor ) are cracked or the vacuum shift motor has a cracked diaphragm and has water in it.
7.Could be the shift plate contacts in the transfer case are corroded / not making good contact, and not activating the solenoids.
{ Picture of Vacuum diagram )

- If the front drive shaft turns:
For ESOF system
-- Check the fuses for the transfer case, engine compartment fuse panel, 17 & Cab fuse panel fuses 13 and 23 ( verify with owners manual, 97-97 & 99-03 MY can be slightly different on some items ).
-- Try hitting the transfer case with a dead blow hammer ( do not use a metal hammer, it can damage the transfer case ) to see if the transfer case shift motor is hung up .
-- Check the transfer case connector, to make sure the connector pins are clean and making good contact.
For MSOF systems
-- Check that the shift linkage on the transfer case is moving when the lever is moved from 2W to 4H and 4L.

May 22, 2011 | 2004 Ford F150

1 Answer

My 98 f150 was in 4WD Hi this morning when I started it. Selector switch is in 2WD position. 4WD Hi light is on, hubs (or front differential) is engaged and transfer case engage. (Feel front wheel hop...


If the switch was in the 2WD position and the transfer case was locked in a 4WD range, my 2 SWAGs would be bad switch or the connector to the shift motor is damaged / corroded or the fuse to the transfer case shift relay module is blown ( fuse # 17 ) / problem with the transfer case shift relay module.

This is without knowing if the truck was used in 4WD the night prior, and shifted out just before turning off. If this is the case, the shift motor might be stuck, and a few hits with a dead blow hammer to the transfer case might jar it free again ( do not use a metal hammer, it could damage the transfer case ).

The vacuum shift solenoids on the firewall are controlled by the GEM ( Generic Electronic Module ) which is grounding either the 2WD or 4WD solenoid, depending on the shift plate contacts in the transfer case. ( when in 4 or 4H, the contact switch plate signals the GEM, which in turn grounds the correct solenoid ).

Pulling the switch will not cause the transfer case to go back to a default position, the switch has a resistance level for each mode, and needs that value to operate the shift motor.

The resistance values for the switch between the 2 dark blue wires:
2WD - 4100 to 3700 ohms
4H - 1050 to 1150 ohms
4L - 380 to 340 ohms
- find the wire locations on the switch, mark them and remove the connector to test the resistance.

Just my opinion on the order :

1. Check the fuses for the shift motor
2. Try the old school shift method, back up ~ 50' put into park or neutral, and shift from 4WD to 2WD.
2.1. This is to see if the transfer case shift motor is bound up, and reversing might release it
3. Try hammering the transfer case with a dead blow hammer while someone shifts from 2WD to 4WD. You only need the key in the run position, if it happens quick enough after running the engine, the vacuum reservoir will still have enough vac to operate the solenoids. Don't chance running yourself over.
3.1. If this frees up the shift motor and the vacuum has bled off, you can try starting the truck and shifting into 4H then back to 2WD to get the front axle to disconnect or manually vacuum operate the front disconnect motor by applying vacuum to the pink vacuum line on the shift motor on the front axle.

Mar 05, 2011 | 1998 Ford F150 Regular Cab

1 Answer

KinlogworksI have A 2003 F-150 Super Crew. I have only used th4 wheel drive a few dozen times. about a mounth ago i switched it into 4 high and nothing happened. problem also in 4 low. any advise?


Operationally vacuum shifts the front axle between 2WD and 4WD mode. The GEM ( Generic Electronics Module ) applies ground to the solenoid needed for the mode selected on the switch ( for ESOF ) or when the transfer case shift lever is moved ( MSOF ). The contact plates in the transfer case signal the GEM that the transfer case is engaged, and the Vacuum solenoids need to be activated ( either 2WD to 4WD or 4WD to 2WD ).

Lift and support the front of the truck so the front wheels are off the ground ( take safety precautions, chock wheels, jack stands, etc )
Key on, engage 4x4 and try to turn the front drive shaft.
- If it turns it is a problem with the transfer case.
- If it doesn't it is a front axle engagement problem.

- If the front drive shaft does not turn :
•With the truck running ( with front wheel back on the ground ), switch from 2WD to 4WD and back again, the vacuum shift motor should move the lever on the front axle.
{ picture of shift motor }
-- If the vacuum shift motor does not move:
•Check for vacuum on the lines while shifting between modes. Pink vacuum line is 2WD mode, Light Blue vacuum line is 4WD.
•Check the fuses for the 4WD system and the solenoids.
•Check the vacuum lines from the vacuum shift motor to the solenoids on the firewall.
•Check the vacuum lines from the solenoids to the vacuum reservoir box behind the battery.
•Check the vacuum reservoir box for cracks.
•Typical solution is the vacuum lines ( to the solenoids or to the vacuum shift motor ) are cracked or the vacuum shift motor has a cracked diaphragm and has water in it.
•Could be the shift plate contacts in the transfer case are corroded / not making good contact, and not activating the solenoids.
{ Picture of Vacuum diagram )

- If the front drive shaft turns:
•For ESOF system
-- Check the fuses for the transfer case, engine compartment fuse panel, 17 & Cab fuse panel fuses 13 and 23 ( verify with owners manual, 97-97 & 99-03 MY can be slightly different on some items ).
-- Try hitting the transfer case with a dead blow hammer ( do not use a metal hammer, it can damage the transfer case ) to see if the transfer case shift motor is hung up .
-- Check the transfer case connector, to make sure the connector pins are clean and making good contact.
•For MSOF systems
-- Check that the shift linkage on the transfer case is moving when the lever is moved from 2W to 4H and 4L.

Jan 18, 2011 | 2003 Ford F150 Regular Cab

1 Answer

2003 F-150 regular cab automatic transmission and the 4WD will not engage.


Operationally vacuum shifts the front axle between 2WD and 4WD mode. The GEM ( Generic Electronics Module ) applies ground to the solenoid needed for the mode selected on the switch ( for ESOF ) or when the transfer case shift lever is moved ( MSOF ).The contact plates in the transfer case signal the GEM that the transfer case is engaged, and the Vacuum solenoids need to be activated ( either 2WD to 4WD or 4WD to 2WD ).


Lift and support the front of the truck so the front wheels are off the ground ( take safety precautions, chock wheels, jack stands, etc )
Key on, engage 4x4 and try to turn the front drive shaft.
- If it turns it is a problem with the transfer case.
- If it doesn't it is a front axle engagement problem.

- If the front drive shaft does not turn :
•With the truck running ( with front wheel back on the ground ), switch from 2WD to 4WD and back again, the vacuum shift motor should move the lever on the front axle.
{ picture of shift motor }
-- If the vacuum shift motor does not move:
•Check for vacuum on the lines while shifting between modes. Pink vacuum line is 2WD mode, Light Blue vacuum line is 4WD.
•Check the fuses for the 4WD system and the solenoids.
•Check the vacuum lines from the vacuum shift motor to the solenoids on the firewall.
•Check the vacuum lines from the solenoids to the vacuum reservoir box behind the battery.
•Check the vacuum reservoir box for cracks.
•Typical solution is the vacuum lines ( to the solenoids or to the vacuum shift motor ) are cracked or the vacuum shift motor has a cracked diaphragm and has water in it.
•Could be the shift plate contacts in the transfer case are corroded / not making good contact, and not activating the solenoids.
sscullys_111.jpg

- If the front drive shaft turns:
•For ESOF system
-- Check the fuses for the transfer case, engine compartment fuse panel, 17 & Cab fuse panel fuses 13 and 23 ( verify with owners manual, 97-97 & 99-03 MY can be slightly different on some items ).
-- Try hitting the transfer case with a dead blow hammer ( do not use a metal hammer, it can damage the transfer case ) to see if the transfer case shift motor is hung up .
-- Check the transfer case connector, to make sure the connector pins are clean and making good contact.
•For MSOF systems
-- Check that the shift linkage on the transfer case is moving when the lever is moved from 2W to 4H and 4L.

Jan 10, 2011 | 2003 Ford F150 Regular Cab

1 Answer

2005 GMC Yukon XL- Service 4 WD light comes on and the indicator light is not lit up nor can I change from 2WD to 4WD. It is push button selection with the option of Auto.


It is probably the encoder motor attached to the transfere case. look under the vehicle to see if there is signs of corrosion between the encoder motor and transfere case.

Nov 11, 2010 | GMC Yukon Cars & Trucks

1 Answer

Transfer case wont engage borg warner 13-56 electronic


if when you press the button to shift into 4 hi, all you hear are a lot of clicks from the control module under the glove box and no indicator lights, that could mean the actuator motor on the back of the t-case is warn(it has no braking ability) so it overshoots its position. this is a common problem. you can go under and hear the motor moving but it seems like it doesnt do anything. sense the module cant get the motor to stop in the correct position, it defaults all the way back to 2wd. a new tcase motor will fix that, you have to splice the wires into the 10 pin connector because from the factory i think 8 wires go to the motor/position sensor and 2 or 3 wires go to magnetic clutch and speed sensor. if there are no click when you press the button, i mean nothing happens, you can run a self diagnostic on the control module by turn the ingnition off, disconnecting the bottom 2 connectors of the 4x4 module (the top connector is the power supply dont touch that one) then turn key on and press the test button on the module (next to the red LED) if the LED lights up and stays on the module is bad. if you press the test button without disconnecting the bottom 2 connectors the led will light and stay on, this is normal and not an accurate self test. turn the key off before reconnecting the module. this advice is of course is assuming you already checked fuses, inspested ALL connectors in the circuit, especiall if a new tcase motor has already been spliced in some years ago, checked power at the switch and module and good grounds.

Aug 10, 2010 | 1995 Ford Bronco

1 Answer

4WD does not engage.


Depending on which transfer case you have, there will either be an electronic actuator or a vacuum actuator that engages the front differential. On the backside of the transfercase there should be a round metal tag bolted to the case. It will have a number on it that starts with NP. Either an NP241, NP246, etc. This will tell you which case you have. Grab a repair manual at an autoparts shop, and it will show you the location of the actuator for the specific case you have. If you have a vacuum actuator, check the vacuum lines going to it first before replacing it. Twelve years does a number on rubber vac lines under a vehicle. You may just have a leak in one.

May 28, 2010 | 1998 GMC Jimmy

3 Answers

Transfer case motor for push button 4x4


i have a 1993 blazer 4.3 w code 4x4 with a 4L60 E . my truck wouldn;t go in 4 hi or low. so i changed the transfer case motor and it works fine now. If you turn the ignition key to on but not crank the engine and open the driver door and push 4 hi button, you should hear the transfer case motor cycle for 3 or 4 seconds every time you push button and the light will flash until it goes in 4wd If the 4 hi button light doesn't flash during cycle then it could be a bad switch. if the transfer case motor won't cycle it could be a fuse or a bad transfer case motor . Hope this answers your question.
pgale89

Dec 16, 2008 | 1994 Chevrolet S-10 Blazer

Not finding what you are looking for?
2003 GMC Sonoma Extended Cab Logo

Related Topics:

39 people viewed this question

Ask a Question

Usually answered in minutes!

Top GMC Experts

yadayada
yadayada

Level 3 Expert

61037 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

21949 Answers

Jeff Turcotte
Jeff Turcotte

Level 3 Expert

6812 Answers

Are you a GMC Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...