Looking for a flow chart for a 2000 silverado

[Golfer]

Had a Service 4WD light come on the other day.  Plugged in the computer which yielded a B2725 code for Active Transfer Case Mode Switch Malfunction.  Ran the datastream and did some testing in the various 4WD modes.

2000 Silverado LT 1500, Z71, 4WD with the 5.3L V8.

The datastream image is here:


It shows the Auto 4WD, 2HI and 4HI lights on when in fact only the 2HI light was selected which is the mode I typically run around in.  I very seldem use Auto 4WD because if I'm going to need it I just use it.  Regardless when this picture was taken it didn't matter which mode was selected and engaged (the 4WD shifts to the different modes just fine and seems to work normally) the datastream showed the lights were on when in fact they were not.  Tested the modes on some loose gravel.  The rear would spin in 2HI, normal.  Floored it in 4WD and it didn't slip a bit taking off in a hurry.  4LO also works.

I now need the flow chart from the Mx Manual to troubleshoot and find out exactly what I need to replace to fix the issue so I was hoping one of our resident experts might be able to point me in the right direction.  My Google kung fu is weak today for some reason and I'm not finding what I'm looking for.  I'm very happy it's not the transfer case making metal or otherwise dying but I do want to make sure I replace the right switch or sensor.

I appreciate the help!

[Fulmar]

Side note: If you took that pic with a camera, turn on the little flower icon.  That's the close-up mode on most cameras ans any close up shots won't be blurry.

[Golfer]

Cell phone camera.  The picture isn't for artistic purposes but thanks for the tip.

[CAP1]

my alldata is down right now. pisses me off when i pay so much for a service that seems to break 2 or 3 times a month.....

anyway, i called a few friends for ya. between all of them, they've replaced about 20 control switches in these trucks.

 i haven't had any of these myself though....but it ashould be a fairly cheap guess,.....you might be able to get it at a napa store, although i suspect you'll end up at the dealer.

 if alldata comes back up in the next 1/2 hour, i'll copy/paste the diagnosis for ya.

[Shuffler]

Might be something to do with the actuator on the front differential that locks it into 4WD. Might check that out.

Took these with my cell phone......





My Daughter with the Beluga Whales at Sea World San Antonio.

[Golfer]

my alldata is down right now. pisses me off when i pay so much for a service that seems to break 2 or 3 times a month.....

anyway, i called a few friends for ya. between all of them, they've replaced about 20 control switches in these trucks.

 i haven't had any of these myself though....but it ashould be a fairly cheap guess,.....you might be able to get it at a napa store, although i suspect you'll end up at the dealer.

 if alldata comes back up in the next 1/2 hour, i'll copy/paste the diagnosis for ya.

I appreciate it Cap.  Your next BFR is paid for. I have a laundry list of things I'm doing to the truck now including front brakes/rotors, new window regulators, A/C compressor and now this switch.

Thanks Shuffler.  I'm very confident that it's not an actual mechanical issue with the differential as the light has nothing to do with it but rather the main transfer case according to the OBDII code.  This makes me very very very very very very very very very very very very happy   The issue is finding the right part to replace with the flow chart.  Cute kid 

Might just sell the thing after all this because I've been eyeing 06-08 Mustangs and my "need" for a truck evaporated after moving to the Philly area.

[CAP1]

I appreciate it Cap.  Your next BFR is paid for. I have a laundry list of things I'm doing to the truck now including front brakes/rotors, new window regulators, A/C compressor and now this switch.

Thanks Shuffler.  I'm very confident that it's not an actual mechanical issue with the differential as the light has nothing to do with it but rather the main transfer case according to the OBDII code.  This makes me very very very very very very very very very very very very happy   The issue is finding the right part to replace with the flow chart.  Cute kid 

Might just sell the thing after all this because I've been eyeing 06-08 Mustangs and my "need" for a truck evaporated after moving to the Philly area.

echelon ford has a gt500 sitting out front. silver with blue stripes. i drool every time i drive past there. especially since black tie auto is right next door.....and they have boatloads of old hot rods. 

come to think of it.....we need a drooly icon here....

[CAP1]

Circuit Description
The range/mode switch circuit consists of four normally open switches. The transfer case shift control module supplies a regulated 8 volt, DC to the switch through the 8 V Reg circuit. The current travel through a 9.09 K Ohms resistor located inside the switch. It returns current to the transfer case shift control module through the switch signal circuit.
The transfer case shift control module constantly monitors this signal voltage to determine the condition of the mode switch circuit. If no buttons are pressed, and the transfer case shift control module detects a voltage level outside the possible range (approx.0.5 to 1.0 volts) for longer than 5 minutes, the transfer case shift control module will set this DTC or it a button is held down or sticks for a period longer than 5 minutes.
When each of the switches is depressed they will complete a circuit through their own specific resistor. The transfer case shift control module continuously monitors the switch input to determine whether the 41-11, AUTO 4WD, 21-11, and 4LO button selections are made by the driver. Neutral may be obtained if the following conditions are met:


The engine is running.
The automatic transmission is in neutral (or the clutch pedal is depressed on a manual transmission application).
The vehicle speed is below 3 MPH.
The transfer case is in the 2HI mode. Once these conditions have been met, pressing and holding both the 2HI and 4LO buttons for 10 seconds will shift the transfer case into neutral, turning on the red neutral indicator lamp.
Conditions for Setting the DTC


The system constantly monitors the voltage on the switch signal circuit.
If the system detects a voltage level outside the possible range produced when no buttons are depressed, (approx.- 0.5 to 1.0 volts), the DTC is logged.
Action Taken When the DTC Sets


All shifting will be disabled.
The SERVICE indicator (4WD/AWD) lamp will be latched on for the remainder of the current ignition cycle.
Conditions for Clearing the DTC


The transfer case shift control module will clear the current DTC if the condition for setting the DTC no longer exists.
A history DTC will clear after 100 consecutive ignition cycles without a fault present.
History DTCs can be cleared using a scan tool.
Test Description
The number(s) below refer to the step number(s) on the diagnostic table.


Tests for proper operation of the transfer case mode select switch.
Tests for proper voltage supply to the transfer case mode select switch.
Tests the transfer case mode select switch for proper resistance values in all switch states.
Tests the switch signal circuit for a short to voltage.
Tests the switch signal circuit for an open or short to ground.
Tests the switch signal circuit for a short to the 8 V Reg circuit.
Determines whether the 8 V Reg circuit is greater than or less than the specified voltage.
Tests the 8 V Reg circuit for a short to voltage.
Tests the 8 V Reg circuit for an open or short to ground.
 
 






ok...the above describes the pics i'll be putting in the next reply.

[Golfer]

I'll take a convertible, V8, auto or manual matters not.  Manual is probably better because it's one more excuse not to let girlie drive it .  One of the guys I fly with is into drag racing his '04 Vette but my money pit is going to have wings and aerobatic capabilities.

Just saw your post.  Awesome!  Awaiting the photos.  Thanks again 

[CAP1]

the wiring



part of the flowchart...i may have reversed them.....but they're numbered.......



just felt typing aomethign here.....



and finally, i just felt the need to put this pic in......it's my next weeks backround on my home office puter.

[CAP1]

I'll take a convertible, V8, auto or manual matters not.  Manual is probably better because it's one more excuse not to let girlie drive it .  One of the guys I fly with is into drag racing his '04 Vette but my money pit is going to have wings and aerobatic capabilities.

Just saw your post.  Awesome!  Awaiting the photos.  Thanks again 

nooooo problem sir!!

i have my 68 camaro......but to be honest, if someone came along and offered me enough to saaayyyy.......buy even just a measly 152......that car would be gone tomorrow. especially if i could get my hands on an aerobat.
 i don't have the knowledge or skill set to fly anything beyond normal maneuvers.....but that would be one helluva incentive to fix that problem, eh?

 as for the bfr......that would be VERY appreciated. i think it'd be interesting, and a great learnign experience to fly with you even if not for that.......just from reading some of the things i've seen you post.

keep us up to speed on the truck?



john

[Golfer]

I appreciate it.  What's step 5?  Those last two look like the same image.

[CAP1]

I appreciate it.  What's step 5?  Those last two look like the same image.

 

i'm an idiot sometimes!!




almost forgot....that looks like an otc scanner?

if so, there should be a "special tests" heading.....you may be able to cycle the motors that control the transfer case through that.....i'm just not sure though.