2002 Chevrolet Tahoe, BTSI Fuse Blows

This 2002 Chevrolet Tahoe came in with multiple complaints so there will be several repairs on this vehicle. The first one deals with the BTSI fuse blowing in the under hood fuse box. I am pointing to the fuse in the picture below.

The blown fuse next to the location on the fuse box legend.

Just in case you could not see which one I am pointing to it in the next picture.

That fuse supplies power to two solenoids on the steering column. One is on top next to the shifter base. The other is under the right side of the steering column. Above the pedal area.

In this next picture you can see some distortion of the insulation on the involved wires. There was a 30 amp “test fuse” and smoke involved in this, at the body shop, before it came to me.

The two harness connectors, which to me, seem very different and should not be easily misconnected.

However there is the proof that they can be improperly installed.

The correct harness connected to the correct solenoid.

I connected the other solenoid and just left it hanging under the dash to confirm the short was gone. It was.

A closer look at the assembly that mounts under the right side of the steering column.

The solenoid mounted back in it’s proper location. It just snaps on the two ball pivot points.

This part of the repair is done but I have a lot more to fix on this Tahoe next week.

2000 Lincoln LS, Rear Window Stuck Down

This 2000 Lincoln LS came in with the driver’s rear window down. A quick check found that the motor was working but the telltale noise of crunching plastic and cables told me the regulator cable was broken.

To remove the door panel, lift the cover in the bottom of the armrest pull handle. Remove the two screws.

Lift the front edge of the power window switch bezel. I used a small screwdriver to help lift the bezel.

In order to remove the wiring for the switch the ash tray has to be removed. Release the latch and push it out.

Now the wiring can be disconnected.

There are two screws along the lower edge of the door panel.

One on the rear edge near the latch assembly.

Now you have to find a good hand hold along an edge and pull the panel loose from the door. You can see the retaining pins on the inside of the panel below.

Carefully peel back the moisture barrier from the door.

Remove the screws for the speaker assembly.

Disconnect the wiring from the speaker and set it aside. Do not place it near any of your screws or you will be looking for screws during reassembly that are now stuck to the speaker magnet.

I removed the screws that hold the silver plate to the door and I also removed the screws that held the regulator to the silver plate.

Once all of the unneeded parts were out of the way, I had a little bit more room to work. In the picture below you will see the plastic bracket that attaches to the glass and the damaged cable dangling from it.

Removing that plastic bracket was a bit worrisome to me. It just felt like too much force would be needed to unsnap it from the glass. So I used a pair of cutters and clipped the front side of the plastic bracket off as shown below.

I then used a plastic pry bar to release the clip on the backside of the glass.

I must say doing it like this took away a lot of apprehension about shattering the glass.

I removed the motor from the old regulator assembly and installed it on the new regulator. I inserted the motor drive gear into the regulator drive socket as close as I could to having the screws lined up. Then I slowly rotated the whole motor until the mounting screws lined up.

The original regulator used a screw but the replacement has a threaded stud, so I had to round up a nut to fit.

In case you were wondering I use suction cup cables to hold the glass in place. I had to attach them to the side of the glass as they would not reach around the upper frame.

The new regulator assembly attached to the inside of the silver panel.

With everything bolted back in place I lowered to glass down to the plastic retainer.

I made extra sure that the peg in the glass was properly aligned with the bracket.

I could not take a picture but I used one hand to steady the new plastic retainer and the other along the top edge of the glass to push it done into the bracket.

I put the moisture barrier back into place and finished installing the door panel and switches. Another one done.

Can You Guess What This Is?

I just had to show this to everyone.  It is just so ridiculous to me that I am not even going to explain what it is for a few days. Take a guess and leave your thoughts in the comments.

Update Aug 22, 2011;  I guess I should have left this up as the primary post for a few days given the response (1). Anyways this is a home made brake light switch. The driver’s is supposed to leave the hook that I am holding, sitting on the passenger front seat. When approaching a stop, the driver picks up the hook and placed it on the hanger loop mounted below the A/C controls. The sad part of the story is that it had a faulty stoplight switch which is inexpensive and easy to change. Not nearly as difficult as hooking up this contraption.

2003 Toyota Camry, A/C Stops Blowing Cold Air

This 2003 Toyota Camry came in with the complaint that sometimes the a/c would stop blowing cold air. Just before it stops blowing cold air the green light under the a/c button will start flashing. I hate to say it but I do not even bother diagnosing this problem anymore. I just go to my parts cabinet and grab a compressor clutch relay and install it.

The relay is in the underhood fuse box.

The lid liner has it listed as “MG CLT”, an abbreviation for magnetic clutch. You may need to click on the picture below to enlarge it.

The magnetic clutch relay is the short white relay  in the center of the picture below.

A simple extraction.

The new relay.

The new relay installed.

The a/c is back working as designed with no problems.

You know at the beginning I stated that I do not even bother testing these anymore but I actually do. It just does not involve tools. First I have to induce the problem to confirm it exists. To do that I set the a/c to full cold and the blower to the lowest position. Roll the windows up and let the engine run while I go about my business. I listen in the back ground to see if the compressor stops cycling off and back on. When I notice that it has failed to come back on, I install the new relay. Operate the car under the same conditions and confirm the problem has been corrected.

1993 Honda Civic, Blower Does Not Work

This 1993 Honda Civic came in with the complaint that the blower motor does not work on any speed. The blower motor is located under the passenger side of the dash. I depressed the thumb latch and pulled the connector from the blower motor.

I checked power on both wires and nothing was there. key was on and the blower switch was set to high.

There should have been power on the blue/white wire. The blue/black wire is the ground control wire. It feeds through the blower switch and blower resistor.

I looked at my wiring diagrams and discovered there  was a blower relay in the underhood fuse box. That fuse box is located under the hood on the passenger side of the vehicle.

The blower relay is located in the top center of the picture below.

The blower relay.

I am using a simple test light for the following tests because I had already checked the wiring diagrams and determined it was safe for a testing. On many systems a test light cannot be used due to possible damage to electronic modules. Ignition power from the interior fuse box.

Constant power from the blower fuse that is located just below the relay.

Notice in the next pictures that my test light lead is attached to battery positive. When the tip of the light is touched to ground the bulb will light up. In this case I am checking a return ground from the blower motor.

Constant ground for the relay coil.

I jumped the terminals from blower fuse to the blower motor. The blower worked. Please keep this one fact in mind. I know exactly what is on the other end of a terminal before I jump a circuit. One wrong move and you can cost yourself thousands in repairs. I had already looked at wiring diagrams and had determined that there were no electronic modules of any kind connected to these four terminals.

Just in case someone needs to know the ignition feed fuse in the interior fuse box. Fuse #13.

The new relay on the left and the old one on then right. There are clips on both sides that hold the relay in place. Kind of a pain to release. If you just pull firmly and wiggle the relay it will release. One of the clips will generally break in doing so though.

You may also notice that there are three relays in the underhood fuse box that all have the same part number. If you want you can take the one out for the rear window defogger to test with.

Reinstalling The Passenger Side Hush Panel, 2005 Cadillac Escalade

On this 2005 Cadillac Escalade I had to replace a faulty driver’s blend door actuator. Ironically it is mounted on the passenger side of that dash and requires removal of the lower hush panel. If there is no floor mounted center console there is no problem with removing and installing this panel. If there is a floor mounted center console, the screw over the transmission hump in the floor pan is a little difficult to remove but nearly impossible to install.

I have fought with this issue for sometime now and finally decided to come up with a better plan for installing that screw. The solution seems to be to make the recessed hole smaller by installing an insert of some kind. In this case I used a starter bushing. It was handy and worked well. The hole needs to be reduced enough so that the screw will not go into the recessed ring at the outer edge of the hole.

This bushing measures .975″ OD, .76″ ID and 1.126″ in length. I am fairly sure that a short piece of thick wall PVC pipe or rubber hose would work as well. Maybe these measurement will help you find something laying around in your garage that will work for you. .

A little bit of weather strip adhesive on the hex. I do mean just a very little bit. I had to remove some of the excess from this one. Just enough to make it stable in the socket.

Insert the bushing/spacer. Place the socket with screw up into the recess. Use your free hand to pull the hush panel back slightly towards the seats. Then screw it in. It took me two tries to realize that I had to pull the panel back some.

On the third try it went in perfectly. I am pretty sure I will be able to do it on the first try next time.  Somehow I managed to line everything up just right to take a picture of the installed screw.

This repair will apply to all GM full sized trucks and suv’s from the 1999 new body style to the 2007 classic series that have this hush panel and the factory floor mounted center console.

Scan Tool Will Not Communicate / Power Up

Although the vehicle I am working on is a 2005 Cadillac Escalade, this information is relevant to many OBD2 vehicles. The Tech 2 makes it simple because the tool does not have it’s own battery supply. therefore if the scan tool will not power up there is a basic problem with power or ground to the DLC. Many scan tools now have their own battery supply. When this condition is encountered you generally end up at a screen that states that the module will not communicate. Not a big deal if you know your tool and realize you need to check those circuits. Unfortunately many times a technician is thrown off by this and starts looking for problems with the data communication lines. Yes, I have had this happen to me as well. Once you learn the lesson the hard way, you don’t forget.

As I stated earlier this particular vehicle is a 2005 Cadillac Escalade, but this relates to Cadillac, Chevrolet and GMC  full sized Trucks and SUVs between 2003 and 2007 Classic series. So if you have an Avalanche, Escalade, Silverado, Sierra, Suburban, Tahoe or Yukon this applied to your vehicle as well.

I have done this so many times that I went straight to the blown Lighter fuse in the underhood fuse box.

Yes, the fuse was indeed blown. On the fuse box legend, just to the right of the blown fuse is a fuse location marked CIG LTR,  15A. That is the location of the fuse in the fuse box. If you click on the picture below and enlarge it it is much easier to read. You may also notice that this applies to the H2 Hummer as well.

Now we have power at the scan tool and I can proceed with checking the original customer complaint or hot air from the driver’s side vents. For you future readers it is August in South Carolina. Not a real good time to have 140 degree air blowing at you.

2005 Cadillac Escalade, Driver’s Side Vents Blow Hot Air, A/C On

This 2005 Cadillac Escalade came in with the complaint that the driver’s side vents have switched to blowing only hot air with the a/c on. The passenger side air is cold.

The telltale B0408 code for a faulty driver’s side blend/ temperature door actuator. Granted most people do not have a dealer level scan tool to work with, but there are ways around that. I will discuss that later.

The repair begins with removing the passenger side lower dash hush panel. There are three screws that hold this panel in place and all three have to be removed to replace the actuator.

The first one is easy.

The second one will not accommodate a power driver so I had to switch to a ratchet.

The third one is a little difficult.  A standard ratchet will do the job but this little 1/4″ drive palm ratchet makes it easier for me.

Getting that third screw out is difficult but re installing it properly is near impossible. The hole is slotted and there is a recessed ring at the outer edge of the hole.

Okay the panel is now out of the way.

To do testing with a voltmeter at the harness connector you will need to test the following.

Check for ignition power on the brown wire. If power is not present check the HVAC 1 fuse in the left interior fuse box.

Check for a 5 volt reference signal on the light blue/black wire.

All of the following backprobe tests must be done with the harness connector plugged into the actuator. 

The yellow wire is a low reference circuit from the control head (ground, technically internal system not chassis).

The light blue wire is the position signal wire from the actuator to the control head. If the actuator will move when commanded the voltage will change up or down depending on the movement of the actuator (nominally between 0 and 5 volts).

The dark blue wire is the command circuit from the control head to the actuator. It will have basically three different voltages that are important:

.5 volts is a signal to increase the door position,
0 volts is a signal to decrease the door position
2.5 volts is a signal to hold/stall the door position.

So with that information turn the ignition on and touch the black lead of your voltmeter to the yellow wire. Touch the red lead of your meter to the brown wire and check for a reading of battery voltage.

Follow that up by having your black lead on the yellow wire as before and now place the red lead on the light blue/black wire. You should see a 5 volt reading on your meter.

These two tests are to confirm a valid low reference signal on the yellow wire, ignition voltage on the brown wire and a five volt reference signal on the light blue wire. If a nominal 12 volt and 5 volt reading are not found further testing will need to be done using a known good chassis ground.

Assuming the above tests went okay the next step would be to test the command circuit on the dark blue wire.

With your black lead still connected to low reference or a good chassis ground, touch the red lead to the dark blue wire and check for either 0, 2.5 or 5 volts depending on command. You will probably need an assistant to adjust the temperature control for the driver’s side.

If a hard code is stored the command signal may be locked. This would be evident if you are using a scan tool. If you are not you may need to clear the presumed codes by performing a system recalibration. A system recalibration involves removing and reconnecting the battery /memory circuit for the HVAC control head.  Recalibration Procedure.

Also if the HVAC control head does not receive the proper position feedback signal from the actuator withing two minutes of the ignition being turned on the command signal will be locked.

Testing can also be done at the junction block at the passenger end of the dash. It is not as accurate as testing at the actuator and the HVAC control head assembly but it is easier. It lacks accuracy because it is done at a midpoint  of the components. Link to junction block testing.

Assuming that testing has determined that the actuator is indeed faulty and you are going to replace the actuator, you can save yourself some grief by keeping a couple of things in mind.

If your old actuator is still working some of time, you may want to try this. Using a small mirror, adjust the driver’s temperature until the old actuator is as close as possible to the new actuator position.  Remember that the image is backwards and double check it against a point of reference. DO NOT try to adjust the new actuator to match the old one. If the new actuator is connected to the harness in an attempt to do that, it may over travel and stick in that position.

Finish removing the old actuator assembly.

The new actuator generally arrives with the notch in the shaft centered on the middle hash mark. That would be the position you would like for the old one to be indexed at before removal. If it is still working.

In one of the earlier links about testing at the passenger junction block, there is also a method for moving a stuck actuator. I would strongly recommend consulting a wiring diagram and connector pin out specific to your vehicle. GM does move some of the wires in various years and models. 

This one would not move and the system will need to be recalibrated after the new actuator is installed. On the old actuator the notch is slightly past the right hash mark. Also the part number on the two actuators have changed, 52402588 on the old one and 89018365 on the new actuator. If you want to purchase the most up to date actuator for this truck

please click here.

Note the commanded and actual positions on the screen below.  This is the reason for having to recalibrate the actuators.

After the recalibration is done the numbers will be a close match. Not always an exact match though. The reason I am trying to steer you towards aligning the old actuator to the new one is this. You have already had one actuator fail. The rest of the actuators are just as old as the one that failed. If you perform the recalibration procedure, all of the actuators are calibrated and not just the one you replaced. This opens up the possibility of other failing actuators becoming stuck. There are four actuators in all. If you are a DIYer finding these other failing actuators may not be convenient to your finances or HVAC needs. If you are doing this for someone else you need to make the vehicle owner aware of what might happen. Think of DIYer concerns.

Re installing the hush panel is a little bit of a pain in the rear but I did a post that shows how to make it a little easier. Please click here to see.

HVAC Actuator Recalibration Procedure For GM Trucks and SUVs

The topic of how to perform the actuator recalibration procedure on Chevrolet , GMC and Cadillac Trucks and SUVs has become an ever increasing topic of discussion.

For manual systems it does not matter where the a/c controls are set but if you feel the need to do something, turn the blower switch on (I prefer speed 3) and set the temperature sliders about .5″ to .75″ from full cold.

For auto systems, press the auto button, with the key on.

Turn the ignition off.

Remove the HVAC/ECAS , 10 amp fuse in the underhood fuse box* or disconnect the battery for one minute.

DSC04801

*Fuse locations can vary from year to year and between different models. Hopefully I will be able to build a list for this.

Install the HVAC fuse or reconnect the battery.

Start the engine. On systems with auto a/c controls the controls will default to 74 degrees F when the ignition is turned back on.

DO NOT TOUCH the a/c controls.

Let the engine run for 1-2 minutes.
Turn the ignition off for at least 10 seconds but no more than 30 seconds.
Restart the engine and then test the a/c controls.

How to Change a Battery Terminal When It Is Part Of A Harness

Although this vehicle is a 2004 Suzuki Verona, this repair can apply to a multitude of manufacturers. The general problem is the battery terminal has failed. The bigger problem is that this battery terminal end is only supplied a part of a larger harness assembly by the vehicle manufacturer.

This repair begins with separating all of the pieces. Pliers and wrenches will be needed and care should be taken as it can be easy to injure yourself.

Once the main components are separated, there may be a bolt or nut that is part of the cable that needs to be removed. In some cases they are pressed or brazed on. On the bolt, you can use a setup like I have in the picture below. It may take quite a bit of force.

This one had rolled over tabs holding it in from the back side. A pair of pliers and a screw driver took care of those. Some have a nut that will be crimped or brazed into position. The same setup I showed earlier will work most of the time on those designs. Sometimes it is easier to drill it out/off though.

The back side of the battery cable end.

The replacement battery terminal has a larger diameter post that the original bolt, so the hole will need to be enlarged.  I use a stepped drill bit because it makes a clean hole. Also I use one that has a damaged tip that is fairly useless for anything else. I would not use an expensive bit like this normally due to acid concerns.

Now it is time to clean and flatten the terminals.

The brush in the picture works great attached to a cordless driver. I used a pair of flat jaw pliers to squeeze the metal back flat.

The final assembly. looks pretty good to me.

This one is done.