A/C Compressor running constantly on my '99 hoe

[SunlitComet]

Just call me 925-207-8795 I will be at my truck.

 

[gpracer1]

Just call me 925-207-8795 I will be at my truck.

Now THAT is service !!

 

[willie1280]

sorry, missed the part with your phone number. What would be a good time to call you today (Wed)?

A few things i noticed on the way into work today with temp around 73deg 94% humidity.
-With all the dials turned off on the temp control panel, air is still pumping out pretty decent from the defrost ducts. I thought i correct the issue with me blower not shutting off by replacing the switch for the fan speed control but apparently not.
-I also noticed that even though it's not that hot out, it was very cold just with the air that was unintentionally coming out of the defrost vents.

 

[SunlitComet]

call when you are near your vehicle.

 

[willie1280]

OK, i'll call tonight once i get home and get things situated.

 

[willie1280]

John,
Thanks a ton for all your help today! Unfortunately it wasnt the news i was hoping for.

So when i call the dealer i need to tell then i need the replacement pcm (wether i buy myself. or through them), i need it programmed, vin transfered and what was the third item?

 

[SunlitComet]

Crankshaft Position (CKP) - Variation Learn Procedure CRANKSHAFT POSITION (CKP) SYSTEM VARIATION LEARN PROCEDURE

1. Install the scan tool.
2. Apply the vehicle's parking brake.
3. Block the drive wheels.
4. Close the hood.
5. Place the vehicle's transmission in Park (AT) or Neutral (MT).
6. Idle the engine until the coolant temperature reaches 65°C (150°F).
7. Turn OFF all the accessories. IMPORTANT: If the Crankshaft Position (CKP) System Variation Learn Procedure cannot be completed successfully, refer to DTC P1336 CKP System Variation Not Learned for additional diagnostic information.
8. Enable the Crankshaft Position System Variation Learn Procedure with the scan tool. IMPORTANT: After the ignition switch is turned to the CRANK position, the Vehicle Control Module (VCM) must see a change in the state of brake switch (Released to Applied) to run the learn procedure. Also, the service brakes and the parking brake must be held throughout the duration of the learn procedure.
9. Apply and hold the service brakes. IMPORTANT: While the learn procedure is in progress, release the throttle immediately when the engine starts to decelerate. The engine control is returned to the operator and the engine will respond to throttle position after the learn procedure is complete.
10. Slowly raise the engine speed to 4,000 RPM.
11. Immediately release the throttle when the engine speed decreases.
12. Turn OFF the ignition for 15 seconds after the learn procedure is completed successfully.

---------- Post added at 05:41 PM ---------- Previous post was at 05:38 PM ----------

Also ask them if they are willing to check for a short of that wire between the relay and pcm to see if that eliminates the pcm as the problem. It is easy to do for them.

---------- Post added at 05:42 PM ---------- Previous post was at 05:41 PM ----------

Notes

HVAC Compressor Control Schematics (Part 2 Of 2)

 

[willie1280]

Jon,

The dealer would cost around $600 for everything.

I called Oreillys and they can get me a rebuilt unit for $120 and flash it for $60. If I did this route, would I be able to install it the rest of the way myself??

Matt

 

[SunlitComet]

For you all you do is unplug and un-clamp the unit.There is still the crank relearn to do. If Oreily can't do it shop around for a local repair that can if not then take that task to the dealer where they might give you a break for a ten minute job. di oreily say that it puts in the vin number in the computer memory too and moving the prom/knock sensor module?

Remember technically the truck will still run before the learn prodedure but may act up or throw the engine light at you.

The module gets flashed while in the vehicle. print out the instruction below for the replacement and reprogramming steps to take with you.

---------- Post added at 01:08 PM ---------- Previous post was at 01:08 PM ----------

Control Module Replacement

VCM Harness Connections

VCM Access Cover

Removing Knock Sensor Module From PCM

VCM REPLACEMENT/PROGRAMMING
Service of the VCM consists of either replacement of VCM or reprogramming of the EEPROM. If the diagnostics call for replacement of the VCM, it will be necessary to transfer the PROM and program the EEPROM.

NOTE : When replacing the production VCM with a service VCM (controller), it is important to transfer the broadcast code and production VCM number to the service VCM label. This will allow positive identification of VCM parts throughout the service life of the vehicle. Also transfer the PROM.

CAUTION : To prevent internal VCM damage, the ignition must be OFF when disconnecting or reconnecting power to the VCM (for example, battery cable, VCM fuse, jumper cables, etc.).

CAUTION : In order to prevent possible Electrostatic Discharge damage to the VCM, do not touch the connector pins or soldered components on the circuit board.

VCM REPLACEMENT/PROGRAMMING (WITH KNOCK SENSOR (KS) CALIBRATION PROM)

REMOVAL PROCEDURE

1. Disconnect the negative battery cable.
2. Remove the connectors from the VCM.
3. Remove the spring retainer off and over the rail of the VCM. Slide the VCM out of the bracket at an angle.
4. Remove the VCM access cover.
5. Remove the PROM/Knock Sensor (KS) module.
6. Inspect for the alignment notches of the KS Calibration PROM.
7. Carefully set it aside.
8. Do not open the KS Calibration PROM.
9. Remove the new VCM from the packaging. Check the service number in order to make sure it is the same as the defective VCM.
10. Remove the access cover.

NOTE

• The Knock Sensor (KS) module must be transferred to the replacement VCM.
• The replacement VCM is supplied without a EEPROM program, the replacement VCM must be programmed before the vehicle will run.
• Using the thumb and first finger, remove the KS Calibration PROM by gently squeezing each end of the blue KS Calibration PROM
• Do not remove the cover of the KS Calibration PROM. Use of an unapproved KS Calibration PROM removal methods may cause damage to the KS Calibration PROM or the socket.

INSTALLATION PROCEDURE

NOTE : Press only on the ends of the KS Calibration PROM. Gently press on the KS Calibration PROM until it is firmly seated in the socket. Listen for the click.

1. Align the notches of the KS Calibration PROM with the notches in the KS Calibration PROM socket.
2. Install the KS Calibration PROM in the KS Calibration PROM socket.
3. Install the access cover on the VCM.
4. Install the VCM in the engine compartment.
5. Install the connectors to the VCM.
6. The MIL, antilock and brake lamps will continue to be enabled until the VCM is programmed. Once the programming is complete, the lamps will turn off and normal operation will occur.
7. Connect the negative battery cable.

CAUTION : In order to prevent possible Electrostatic Discharge damage to the VCM, do not touch the connector pins or soldered components on the circuit board.


EEPROM Programming CAUTION : The ignition should always be "off" when installing or removing the Vehicle Control Module (VCM) connectors.

1. Set-up:

• • Battery is charged.
  • Ignition is "ON."
  • Battery/cig. lighter Connection secure.
  • Data Link Connector (DLC) .

1. Refer to up-to-date Techline terminal/equipment user's instructions.
2. If Vehicle Control Module (VCM) fails to program, do the following:

• • Check all VCM connections.
  • check Techline terminal/equipment for latest software version.
  • Try again to program the VCM. If it fails again, replace the VCM. Refer to VCM replacement . See: Control Module Replacement

1. Perform the Idle Air Control (IAC) valve reset procedure with the scan tool. use misc. test.
2. For a functional check perform one of the steps:

• • Use the Techline terminal and equipment in order to perform the On-Board Diagnostic (OBD) System Check

 

[willie1280]

Ok, with vcm plugged in, truck off, compressor plate spins free. Truck on, plate is locked. With pcm didsconnected and truck on, plate spins free.

Ordering new vcm now.