2006 Jeep Grand Cherokee, Blower Only Works On High

This 2006 Jeep Grand Cherokee Laredo came in with the complaint that the blower will only work on high speed. The blower resistor is located behind the glove box area.

I started by removing the two 7 mm screws that attached the lower hush panel to the bottom of the dash.

With the two screws removed, the panel unsnaps from the center and then is pulled out the passenger side of the vehicle.

Then the glove box is opened and the two upper bump stops are pulled down to drop the glove box even further.

With the glove box fully opened the glove box can be lifted slightly and the lower corners of the glove box have to be bumped up to release the hinges from the hinge pins.

The hinge pin.

The hinge hook at the bottom of the glove box.

Now we can see the blower resistor and related wiring.

After unplugging the harness connector from the blower resistor the main problem was quite evident. The damage to the terminal of the blower resistor is harder to see but there none the less.

I used this set up to test for switched ground at the resistor connector.

I used the bleed through power from the blower motor on the light blue wire. I then touched the tip of my test light to the remaining three terminals individually as the blower switch was rotated through the speeds. The ignition switch was of course on during this test. The blower switch circuits tested as okay. Keep in mind that this was an unloaded test and does not guarantee the blower switch will supply the needed amperage to work the blower motor.

Time to start splicing in the new harness connector. I disconnected the fresh air door actuator wiring. Slid the blower motor harness connector off of its retainer and pulled the wire tie clip from the box. Then I had to remove the wire tie hold down and strip the tape from the harness.

Now that the harness is opened up, you can see that the light blue wire, that supplies switched ground control to the blower motor has a splice in it. When the high blower position is selected at the switch the switch sends a direct and full ground to the blower motor. In all other speed positions, the switched ground is sent from the blower switch to the resistor on the remaining three wires. Depending on which speed is selected, the ground signal is sent through one of the three internal  blower resistors. That signal goes out on the light blue wire at the resistor harness connector and over to the blower motor. Thus controlling the blower motor speed.

I started by cutting out the old splice connection and installing a new splicing connector and heat shrink tubing.

I heated the tubing and shrank it into place.

I then continued to cut and splice the remaining three wires. Notice that I staggered the splice joints.

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Then taped the wires back into a harness assembly.

I then connected all of the harness ends and secured in place. The kit I used has a new wire tie to replace the one that I had to cut off. If you would like to purchase one of these kits, please click here.

I made sure every thing was laying properly in place and then pulled the wire tie tight.

All of the wiring repaired and back in place with a new blower resistor.

All blower speeds now worked.

2002 Chevrolet Trailblazer, B0028, B0029 & B0030

This 2002 Chevrolet Trailblazer came in with the airbag light on and codes B0028, B0029 & B0030 for passenger side air bag wiring faults. Something that has had a hard time sinking into my head is, when the scan tool states that there is a problem with a passenger or driver side air bag, SIDE is the important term. It means the SIDE airbag on the passenger or driver side of the vehicle. It does NOT refer to the dash mounted airbag on the driver or passenger side of the vehicle.

I have found a lot of these problems are caused by detailers at used car lots, removing the seats for cleaning the carpet and then forgetting to reconnect the harnesses. A quick look under the seat and I saw the chewed up wiring shown below.

A couple of quick splices.

I then placed the harness back into the split loom and fastened into position. I ran the power seat back and forth, and up and down to make sure the wire was away from moving parts.  I informed the customer that this was considered a temporary repair under manufacturers guidelines. To my knowledge no manufacturers recommend repairing airbag wiring. Instead they recommend harness replacement.

2001 Cadillac DeVille, Multiple Rear Lighting Problems

This 2001 Cadillac Deville came in with multiple complaints with the rear lighting. I will try to describe as much as possible. With the trunk open the license plate and trunk lights would glow. If the park lights were turned on the two previously mentioned lights would go out.

If you click on the picture below you should be able to see the trunk light glowing slightly.

With the park lights turned on the outer vertical strip came on as it should but the top half of the brake light would also come on. Also when the park lights are switched on the remote trunk release would not work.

After looking through wiring diagrams on the different circuits, I decided that the trunk light was probably the easiest to diagnose as its circuits are not controlled by the PZM.  Since the bulb would glow, I knew there was power of some sort at the light. I pulled the bulb out and checked to see which terminal at the light assembly had power on it. I then installed the bulb and connected a jumper wire to the opposite terminal. The other end of the jumper wire was attached to a good body ground. The light worked fine with the grounded jumper wire in place.

I turned on the park lights and they were now working as well. The remote trunk also worked with the park lights on.

A little more checking and I found the broken ground wire at the left trunk hinge harness. There were two broken wires and the red heat shrink told me some one had been there before.

I also found debris in the bottom of the trunk corners that indicated to me that I was at least the third person to fix this problem. My thinking was that the other two repairs probably wound up shortening the wire length, so I wanted to extend the wiring. The most important thing to remember when repairing broken wires in a flex joint like this or a door jamb, is to never make splice where the wires will bend. In the picture below you will see that I went up the hinge arm and made my splices where the wires will be fixed to the metal arm.

On the other end, I went almost to the seat back to start my first splice. Notice also I staggered the joints, so that I would not wind up with a two inch knot of splices.

I had to tape the harness. Secure it to the trunk arm and then place the protective cover back into place.

The finished harness repair. Now, I had to install the interior panels.

This one is fixed.

1995 Chevrolet S10 Pickup, No Dash Lights

This 1995 Chevrolet S10 came in with the complaint that the dash illumination lights do not work. The customer drives a good bit at night and does not want to take a chance on getting a speeding ticket. A quick checked showed that the tail and license plate lights came on, so I knew that the park/tail light part of the circuit was okay. This is important to know. Dash lights are designed to not work  whenever  the tail lights are not working. This is a warning feature to allow the driver to know that the tail lights may not be working and they should be checked.

I checked the illumination fuse located in the fuse #4 position and no power was present. If power had been present and the fuse was good, I would have one of two problems. Either all of the bulbs would have been blown or the common ground would be faulty. No power at the fuse meant that more than likely the panel dimming switch was faulty.

Someone had been in this dash and the trim panel was very loose. I removed the two upper screws.

I found that it was loose enough to pull the corner out far enough to access the headlight and panel dimming switches.

I unplugged the panel dimming switch and checked for power on the brown wire with the tail lights switched on.

Power was present on the brown wire.

I used a fused jumper wire and connected the brown and green wires as shown below.

All of the dash lights worked.

Diagnosis and replacement of a faulty panel dimming switch.

The switch uses two locking tabs to hold the switch in place. You have to lift them a way from the switch to release the locks. The locking tabs on the switches can be seen in the picture above. They are in the middle facing each other.

How To Find Good Mechanic?

I ran across this site today and I think it is a pretty good idea.  I had plans to do something similar in the distant future, but it would seem, that these guys are doing a pretty good job. I wish them all of the success in the world.

Here is the concept as I currently understand it:

Technicians or mechanics can go to the site and build a profile, after taking an automotive logic and reasoning test. They can then give, the customer’s that they work for, the site’s address. The customers leave feedback and rate their favorite technicians. Quality technicians, and the shops that employ them, will gain faithful customers by word of mouth and the www.AutoTechnician.org website

Technicians also benefit from a growing list of automotive resources that they may not even be aware of.

Vehicle owners will be able to locate the best mechanics and the shops that employ them. They also will benefit from a list of automotive resources.

1995 Ford Explorer, Blower Will Not Turn Off.

This 1995 Ford explorer came in with the complaint that the blower motor stays on even with the key off.  The customer had already figured out that the blower fuse could be removed to stop the blower from operating with the key off.

The blower speed controller is located under the hood and below the blower motor. If it is the original design, it can be quite difficult to see. The original connector did not have sealed terminals, so Ford used a rubber boot to seal out moisture from the connector.

To get my hand down to the controller connector I first removed the cruise control servo mounting bolts. Unplugged the harness and moved the servo out of the way.

I had to use a long screwdriver to depress the locking tab and pulled the harness loose from the controller.

To gain more room to work, I also disconnected the wiring harness connectors around the area and moved the harness out of the way.

I then used a long socket and palm ratchet to remove the outer screw.

To remove the inner screw, I used a long extension and swivel attached to the socket (8 mm).

As you can see from the pictures below the blower speed controller has been redesigned.

I had to remove the split loom and tape from the harness to gain enough room to stagger the wire splices.

As you can see it takes some length to splice the wires in a staggered fashion.

I taped the harness back up with the split loom back in place.

Installed the new blower speed controller and connected the harness.

1996 Chevrolet C3500, No Tail Lights

This 1996 Chevrolet C3500 came in with the complaint that the tail lights had started turning off while driving down the road. When it arrived at my shop the park/tail lights were not working at all. I pulled the end of the dash loose to get a quick look at the headlight switch wiring.

I could see some heat damage so I went ahead and disconnected the harness from the switch by first depressing the  locking tab with a pocket screwdriver.

You can see the damage better if you click on the picture below. The top left terminal has been pretty hot as evidenced by the melted plastic.

The wire color has also changed due to the heat. The burnt wire in position “H” was originally orange in color.

To get deeper into the repair, I had to remove the dash trim panel. It has multiple spring clips that have to be unsnapped around the outer edges. Once it is loose the switches that are located to the left of the radio have to be disconnected. They can sometimes be quite difficult.

Once the trim panel was out, I had to flip it over and use two pocket screwdrivers to release the locking tabs that secure the headlight switch to the trim panel. Be careful the tabs can break. With the tabs released, the headlight switch can be pushed on from the front side.

You may need to do the same thing at the other end of the switch. There are four locking tabs in all.

Now that the tape is removed you can see the original wire colors.

The new harness connector comes with all of the wires pre installed. It is usually not very wise to splice all of the wiring so I do things a little differently.

First I remove the TPA (terminal position assurance) clip. There are locking tabs on each end that have to be depressed.

Next using an angled terminal removal tool, I lift the plastic locking tabs for each terminal.

I remove the wiring from all of the cavities that I want to transfer the old wiring to.

Click on the picture below to see the locking tabs for the terminals.

All of the good wiring is now installed in the new connector body.

Time to splice the remaining wires into place one at a time.

A little heat to shrink the tubing in place.

Wrap the harness back up to secure the wiring.

A new switch and now all that needs to be done is to assemble in the reverse order.

If you need these parts please click here.

2004 Chevrolet Trailblazer No Stoplights

This 2004 Chevrolet Trailblazer came in with the complaint that the two lower stoplights did not work.  The CHMSL (Center High Mounted Stop Light) does work. I installed my pedal pusher between the brake pedal and the front edge of the seat.

I went to the fuse box under the driver’s side, rear seat and checked the vehicle stoplight fuse.

Power on both sides of the fuse, so the problem is further back in the vehicle.

Yep, the CHMSL is working but nothing else.

I removed the two phillips headed screws that held each light assembly in place and pulled the light assembly away from the rear of the vehicle. After the light assembly was removed, I removed the three screws that held the socket board to the lens. Once the socket board was off, I pulled out the upper most bulb for the stop light and this is what I found.

On these vehicles, I prefer to use a high quality plastic based bulb rather than the glass based bulbs.  These vehicles came with the plastic based bulbs originally. The plastic tends to insulate the socket from the bulb heat. The glass bulbs seem to transfer more heat into the socket and melt both parts.  To help keep this problem away on any vehicle, place the shifter into park or neutral and take your foot off of the brake pedal, when stuck in a drive through lane or stopped traffic. Of course keep safety in mind as well.

I replaced the boards and installed three new bulbs in each board.  Heat damage is like a disease, you have to get rid of it all or it will come back. Whenever I check one of these type bulbs, I look for even the slightest signs of heat. One trick is to rub my finger length ways, along the wire leads and feel for rough surfaces. If I feel any kind of roughness, a new bulb is installed and the socket is inspected, cleaned and or replaced, depending on what evidence is present.

The old board had not been properly screwed down and as a result the opening in the lens assembly was distorted.

After installing the board (I had to find one larger screw), I used silicone sealer to fill the gap between the  orange gasket and the lens assembly.  I did not want water to get into the assembly.

Now all three stoplights work.

1996 Ford Explorer, Intermittent No Crank Condition, Engine Stalls

This 1996 Ford  Explorer came in with an intermittent no crank condition. Followed by a stalling and no re crank condition.  The customer told me that he had fixed the battery cable connections. Well yes, there was a new negative battery terminal installed.

I have mixed feelings about these painted battery terminals. I dislike them, because they are such poor conductors of electricity and cause so many problems. On the other hand, so many people are compelled to use them, and because they cause so many problems,  I have a lot of work fixing the condition properly.

The customer was fairly ingenious, in that he had cut the loop off of the old terminal and reused the bolt, along with the remaining nut, to hold the cable to the battery terminal. He failed to realize that paint is an insulator and has no business on any unassembled electrical connector. He also failed to do any kind of cleaning to the old terminal.

Now for my way of fixing this problem. I first cleaned the battery post and then installed a marine style battery terminal. Note that the nut insert will not fit over the terminal stud.

Using a drill bit, cordless drill and a pair of pliers to, hold the cable with, I removed the crimps. Then pulled the nut, off of the cable with a pair of pliers.

Now, the hole is large enough to fit over the stud. I used a pair of pliers to flatten the metal. Sure looks bad though.

I used a pair of side cutters and a coarse file to round out the metal and remove the sharp edges.

Next, I used a cordless driver and one of my favorite battery brushes to clean the terminal. If you want one of these brushes they can be purchased here.

< Now, the metal actually looks more like a terminal than a raggedy, corroded piece of crap.

I installed my newly crafted battery cable terminal onto the marine style battery terminal stud.

The engine now cranked and ran normally.

1994 Subaru Legacy, Blower Does Not Work

This 1994 Subaru Legacy came in with the complaint that the blower does not work at all. I checked for power at the fuses and battery power was present. I went to the blower motor and checked for power on the black/red wire and it was not present.

I started looking for the blower relay. It is located above the driver’s side fuse box and is quite difficult to find. So hard that I could not get a picture of it without removing the dash but it is up there.I did luckily notice some heat damage on a connector at the lower right corner of the fuse box.

Now, this car really needs a new fuse box and a harness connector. It is however sixteen years old, with about 180,000 miles on it. Some investigation found that most of the heat damage was done to the female terminal in the connector and that the male terminal in the fuse box looked pretty good. I consulted with the customer and we decided to try a good patch. I found a terminal in my collection, that fit well. I crimped and soldered it to  a piece of 10 gauge wire.

I installed the new wire lead onto the appropriate terminal in the fuse box. Then I cut the corner off of the plastic male connector.

Installed the harness connector around the new lead.

Installed heat shrink tubing and splicing connectors.

Crimped and sealed in place.

Tucked the wire into the harness so that it would be held in place, by the tension and weight of the harnesses.

The fuse that I show in the following picture as well as the matching fuse behind it are for the blower motor and are powered at all times. These two 15 amp fuses supply power to the blower relay, which when activated by the ignition switch sends power out to the blower motor on the black/red wire that was damaged at the fuse box.