Auto-Dimming Mirror(s) upgrade

[PaulP]

I just moved from a 2002 Envoy to a 2005 Trailblazer. There were a number of de-contented items I wanted, one in particular was the AutoDimming mirrors.

I checked the pin-outs and changed my interior rear view mirror for one from a 2004 Silverado. OnStar and AutoDimming works fine. But the temperature display doesn't. I have the LT version which has the exterior temp built into the heater controls. I am confident there is just a wire missing somewhere, but looking for any input on where.

Checking the connector at the mirror, the wire and connector for the ambient temp sensor is present there. Per the shop manuals, it runs to the rear fuse block.

I haven't chased it past there. Has anyone else done this mod or can you give me ideas to check where the wire connection is missing?

Once this is operational, I am then on to the exterior auto-dimming feature for my drivers side mirror.

Paul P

[04TBEXT]

Paul P: I come upon this information regarding ambient temperature displays referencing 02-05 Buick, Chevrolet, GMC and Oldsmobile Mid-Size Utilities (GMT305, GMT360 & GMT370) chassis. I don't know if this will apply to what your doing...hope it helps.

VEHICLE: 02 -05 Mid -Size Utilities as referenced above with RPO CJ2 Ambient Temperature Display.

CONDITION: Inside rear view mirror does not display outside ambient temperature.

RECOMMENDATIONS: When equipped with CJ2 (automatic HVAC control) the ambient temperature will display in the climate control head. The rear view mirror will not display any temperature. If the vehicle is equipped with CJ3 (manual dual zone HVAC control), the optional inside rear view mirror (RPO DF5 or DD5) will display the outside temperature. This is a design intent. DO NOT try to install a rear view mirror that will display an outside temperature (DF5 or DD5) on a vehicle with CJ2 (automatic HVAC control).

Excerpt from GM Service Document ID#1549108 (#PIT3151) dated 9/10/04.

Paul, I'm not that good with the electronics, but I think this redundancy would cause some type of electronical dysfunction within the BCM (body control module) which is responsible for all of these duties. Let me know if this helps.

[PaulP]

O4TBEXT,
Thanks for the lead on the document. I am digging a little deeper into si2000 to get more info. Your document number will help.

Electrically, other than a missing wire, there should not be a problem. It is only a circuit reading a voltage amount controlled by the ambient air sensor. Whether that voltage is read by one or 20 circuits, it won't matter.

GM often includes wiring in the harness, whether the option is included or not. The problem is figuring out which wires are included and which are not. Ran into this in my Envoy with the exterior Auto-dimming mirrors. The entire circuit was included with the vehicle, except 24" of wire in the drivers door. Once I added this, then that mod worked perfectly.

Are you a GM tech? Have you been into the body harness of the Trailblazer? Do you know the path the harness takes between the front mounted ambient sensor (near the radiator) to the rear fuse block?

Paul P

[XTREEME]

While we are on this topic, why is it that GM cheaped out and stopped putting the Auto-Dimming mirrors in?

Is it just the TB/Envoy line, or the whole GM vehicle line?

[Dave]

Auto dimming is one feature I love. It doesn't matter how many ricer cars have their high beams and driving lights on behind you.

[Tommy]

While we are on this topic, why is it that GM cheaped out and stopped putting the Auto-Dimming mirrors in?

Is it just the TB/Envoy line, or the whole GM vehicle line?

The Trailblazer is the first vehicle I ever had that didnt come with a glovebox light. I had an 02 and now have an 04 LT. Talk about cheap.

-Tommy

[Black Ice]

Im going to take it one more step Tommy.. why didnt they put the underhood lamp in alot of the TB's on mine you see were it is suppose to go but its not there.. Crazy

[Tommy]

Im going to take it one more step Tommy.. why didnt they put the underhood lamp in alot of the TB's on mine you see were it is suppose to go but its not there.. Crazy

Yeap me too, 04 TB LT with everything but sunroof, and no light under the hood or in glovebox. LOL Its probably a .25 cent part.

I wonder if the envoys haves lights in those places..."Professional Grade"...they should.

-Tommy

[Envoy Fan]

I wonder if the envoys haves lights in those places..."Professional Grade"...they should.

-Tommy

Dark under my hood and in my '03 Envoy glove box. But, but, GMC did figure out how to put a big sliding rear roof on the XUV.

[Tommy]

Wow,

I can't believe it, GM cheaped out on the Envoys too.

-Tommy

[XTREEME]

Have you also noticed how the D.I.C. has about half of the functionality it had just a couple of years ago? Its just very basic information now in the 2005 models.

(ie. no more Instant MPG, no more Avg MPG on trip settings - actually nothing for trip settings now except the actual trip mileage itself).

[04TBEXT]

Paul P. You say you have SI2000 access? By using SI2000, this is what I see. The wiring harness leaves the sensor under the hood, travels down, then left under the left headlamp. It then turns rearward and travels over or around the left wheelhouse toward the cowl. I suspect the wiring harness enters through the cowl somewhere around the steering column. It then travels down the floor pan, inside the vehicle, at the dead pedal area and along the left inner side of the rocker panel until the reaches the BCM area under the left rear seat. I again suspect the wiring harness comes up through the carpeting @ the BCM. You will find these routing schematics in SI200 under STATIONARY GLASS/INSIDE REAR VIEW MIRROR and MAIN BODY/WIRING HARNESS ROUTING. If you do this, you might try following the wiring color codes of the wiring from the ambient sensor as it travels to the BCM. Hope this helps...let us know.

[Dave]

How about using a manual hood support rod? Even my 00 Grand Prix's hood doesn't use a rod.

[02EnvoySLE Guy]

Wow,

I can't believe it, GM cheaped out on the Envoys too.

-Tommy

My '02 Envoy doesn't have a light either. And the light under the hood doesn't work for some reason.... hmm....

[04TBEXT]

Totally agree with all of you...a considerably priced mid-size SUV without some basically low-cost features. We're not talkin' power floor mats or reclining ashtrays here. I wonder if these items are found on a comparatively-priced import SUV. Three years before a real SSR appeared, a disappointingly-styled GTO, 05 Ford Mustang, Ford GT, anything with a "HEMI"...Hey GM!... time to wake up!

[Dave]

Maybe they scaled back on the DIC because the NAV system is now available. It still isn't a good excuse.

I think GM figures that few people will notice the items that we pointed out. Most people don't even know how to check an oil dipstick so the hood light and support were probably low priority to GM.

Interiors on most GM cars are also disappointing. I think the Trailblazers should be better.

[Tommy]

Interiors on most GM cars are also disappointing. I think the Trailblazers should be better.

The quality of leather they used for the seats is a big disappointment. Looks and feels like they skinned the cow at the dealership.

Also, did you notice that they did not use any covers over the bolts where the front seats attach to the floor? They sure made the cut-outs in the carpet so large around it that it sticks out like a sore thumb if you have your seats all the way back.

My LT stickered for $36,225, with the GM supplier discount from my work and incentives, I got it for $28,200 (tax included) with extended 6 year-60,000 warranty and free oil changes for 3 years. I bought it on the last day of the month, seems to be the best time to buy. They need to make that quota.

-Tommy

[Envoy Fan]

The quality of leather they used for the seats is a big disappointment. Looks and feels like they skinned the cow at the dealership.

-Tommy

The Envoys with leather actually have some cloth on the front seat insides next to the console. This is even on the new '05 Envoy Denalis.

No wonder lot of folks refer to GM leather as pleather (guess this is a combo of plastic and leather, as there is a lot of vinyl on the GM leather seats)

[04TBEXT]

Another thing needed to think of when speaking of leather seats, is the need to carefully read the propaganda. When GM speaks of leather seats in their literature, etc, they refer to "leather seating areas". What this means is that the only portion of leather in the seat covers are the portions that your "butt" and back touches. The sides and back of the seat back cover and sides of the seat bottom cover are vinyl.

[captdan27]

PaulP;
Did you ever get the temp sensor routed to the mirror? I have an '05 that I did the same thing you did, and have the same problem.

[PaulP]

CapnDan
Sorry, been lazy. I've traced the wiring to the rear fuse panel but haven't taken the time to trace it any further.

Best I can tell, the ambient circuit gets routed to the back of the HVAC switch on LT models. Pretty confident I can get the circuit to work by putting a splice at the right spot.

Just haven't had time to do it.

I'll post the results in the near future

Paul P

[dwpoyner]

Hey guys! New to this board. I jsut bought an 03 LS TBlazer. I love it so far. I as well really like the autodim mirror. I installed one in my last car. My question is when you put this mirror in, where does the wire harness plug into above the headliner? Before when I installed a mirror, I just snagged power and ground from the lights. This one looks a bit more complicated. Any suggestions?

[ScarabEpic22]

Welcome! I cant really answer your question, but I have another for anyone to answer. I see in one of the earlier posts, that the Envoy had an autodimming mirror function on the side mirrors? I know my TBs rearview mirror is autodimming, but I have never heard about the side mirrors dimming on an Envoy. If so, what is needed to make the non-autodimming capable, without buying a whole new mirror assembly.

Thanks,

[homertime]

Totally agree with all of you...a considerably priced mid-size SUV without some basically low-cost features. We're not talkin' power floor mats or reclining ashtrays here. I wonder if these items are found on a comparatively-priced import SUV. Three years before a real SSR appeared, a disappointingly-styled GTO, 05 Ford Mustang, Ford GT, anything with a "HEMI"...Hey GM!... time to wake up!

Whenever I think competitively priced import I think the 4-Runner:
Here's what you don't get with the 4Runner (SR5 and Sport i'm not sure about the limited):
No DRL or automatic sensing lights
No heated mirrors
No electrochromatic mirror
Cheap looking clock
DIC is also cheap with even fewer options then we have
Not quite cloth but not quite parchment seating surfaces
I don't recall a glove box light
Less power (260 hp max with v8, 245 in v6)
and the list can go on

I believe the Limited, which can go for like $38,000 has everything you can think of...
I admit we do have somethings bad, but not THAT bad... yet

When they start putting the spare tire as an option, we can start worrying.

[FattyTBEXT]

When they start putting the spare tire as an option, we can start worrying.

You can say that again. Or if they put the spare tire on the back like the new, underpowered H3. Spare tires on the back are so K5 Blazer, IMHO.

Like "Hmmmm, we didn't plan the undercarriage well enough to have room for a spare tire. I have an idea, let's put it on the back of the truck." :m2:

[rcam81]

Why didn't GM put the I-6 in the H-3? I saw one yesterday and it reminded me of my old '92 Blazer with the tire on the back. I wonder if it rattles like that one did?

[bravy02]

The Envoys with leather actually have some cloth on the front seat insides next to the console. This is even on the new '05 Envoy Denalis.

No wonder lot of folks refer to GM leather as pleather (guess this is a combo of plastic and leather, as there is a lot of vinyl on the GM leather seats)

I believe that the cloth on the front seats that touches the console possibly prevents the leather/vinyl from dragging and getting scuffed up when the seat is moving back and forth? :undecided

I own a 2002 Bravada AWD and this vehicle too has the cloth on the leather seats. I do have a light under the hood with the crappy prop rod. I also DO have a light in my glove box.

I couldn't believe that for a vehicle that stickered for $38,000 and some change there was no under hood prop rod. I owned a 1997 Grand Prix GTP that had hood struts but no hood light. I'd honestly rather have the hood struts and add the under hood light or use a dang maglight. Sometimes I just don't understand GM.

I do give thanks to GM though for molding the Bravada/Rainier into the new Saab 9-7x because most of the sheet metal is exactly the same (when compared to a TB/Envoy). I was able to order the Saab 9-7x Euro Tail lights which fit perfectly on my Bravada :laugh:

EDIT: for spelling.

[Envoy Fan]

Why didn't GM put the I-6 in the H-3? I saw one yesterday and it reminded me of my old '92 Blazer with the tire on the back. I wonder if it rattles like that one did?

Not enough room under the hood for the long I-6. :m2:

[Envoy Fan]

I believe that the cloth on the front seats that touches the console possibly prevents the leather/vinyl from dragging and getting scuffed up when the seat is moving back and forth? :undecided

I own a 2002 Bravada AWD and this vehicle too has the cloth on the leather seats. I do have a light under the hood with the crappy prop rod. I also DO have a light in my glove box.

I couldn't believe that for a vehicle that stickered for $38,000 and some change there was no under hood prop rod. I owned a 1997 Grand Prix GTP that had hood struts but no hood light. I'd honestly rather have the hood struts and add the under hood light or use a dang maglight. Sometimes I just don't understand GM.

I do give thanks to GM though for molding the Bravada/Rainier into the new Saab 9-7x because most of the sheet metal is exactly the same (when compared to a TB/Envoy). I was able to order the Saab 9-7x Euro Tail lights which fit perfectly on my Bravada :laugh:

EDIT: for spelling.

Welcome to the forum. :yes: The Saab tail lights look good on your Bravada.
Great mod. :yes: The Saab has a hood strut, not a prop rod, but I am not sure it could be fitted to other GMT 360s, as the Saab hood is just a little different where the strut connects to it.

[bmm354]

My '02 Envoy has a light in the glove box and under the hood as well. The underhood light sometimes doesn't come on, but tapping on it helps. Not long ago the switches that controlled underhood lights used mercury, which is being phased out from cars. GM went to a mercury-free design with the new lamps and there is a small weight that is supposed to fall/move inside the lamp housing when the hood is raised. It sticks on my Envoy; taking it apart and cleaning it helped for almost a year.

I know I'm in the minority but I really don't have a problem with the prop rod. Maybe it's because I once had a hood slam shut on my head--with the car's engine running--because the gas struts wore out. :mad: I saw stars for a few minutes after that! (Happened on a '93 Chrysler Concorde w/ 95K. That was the final straw and I got rid of it a few weeks later.)

[PaulP]

DW,
You may be hit by the GM lower-base-model blues.

The Trailblazer LS models came in a number of downgraded versions. Some only had a manual mirror, no OnStar.

There is a chance the harness is still installed in your vehicle. You'll need to drop the front edge of the headliner down and look. It normally comes out the front and down to the mirror mount. If you're lucky, it's installed and just tucked up under the headliner.

If not, you've got some major work in front of you

Paul P

[dwpoyner]

DW,
You may be hit by the GM lower-base-model blues.

The Trailblazer LS models came in a number of downgraded versions. Some only had a manual mirror, no OnStar.

There is a chance the harness is still installed in your vehicle. You'll need to drop the front edge of the headliner down and look. It normally comes out the front and down to the mirror mount. If you're lucky, it's installed and just tucked up under the headliner.

If not, you've got some major work in front of you

Paul P

Thanks. I'm prepared for major work if it isn't there. I did an install of an overhead console and automatic mirror in an intrepid that didn't have the wiring or anything there. It can't be too terribly hard. I'll look for a way to lower the headliner and see whats up there though. Thanks!

[tezzmin]

Thanks. I'm prepared for major work if it isn't there. I did an install of an overhead console and automatic mirror in an intrepid that didn't have the wiring or anything there. It can't be too terribly hard. I'll look for a way to lower the headliner and see whats up there though. Thanks!


Did you try this yet? Let me know what you find. I would like to try, but it does sound like it might be over my head finding the locations to splice for power etc..

[bravy02]

Welcome to the forum. :yes: The Saab tail lights look good on your Bravada.
Great mod. :yes: The Saab has a hood strut, not a prop rod, but I am not sure it could be fitted to other GMT 360s, as the Saab hood is just a little different where the strut connects to it.

Envoy Fan...thanks for the comments. I have received many comments about the Saab tailights and feel that it was worth the money...especially for OEM Euro style taillights and not cheap aftermarket ones that will eventually leak.

I will have to look at the Saab 9-7x and see how the hood strut is setup b/c I am curious.

[montecarlo04]

i know in my impala and monte carlo the mirrors are a direct swap

Alan

[DEZEL1]

So I have a 05 TB w/ Onstar & compass. What part# or vehicles can we pull from to gain Auto-Dimming mirror?

[mtt]

Does anyone have an answer to the rearview mirror upgrade for the '05 ? There appears to be many owners with the Onstar/airbag indicator mirror who would like to retain the functionality of those features, while adding autodimming and the temperature/compass feature. Most of us know that the temperature display feature will vary depending on whether you have manual or automatic climate control. Maybe someone with an '06 or '07 can provide the information as to these features in their applications? In other words, if you have some helpful information....Hook a brother UP! (or a sister, whatever the case may be!)

[4havnfun]

Hi,

I'n new to the forums as I just bought an 06 TB LS. I was also missing the auto dimming mirror from the 00 GTP that I traded so I bought an autodimmimg mirror off ebay from an 05 Silverado (without onstar but with compass and temp display) for $46. It plugged right in and the only function that doesn't work is the temp display (which is reading OC). The airbag indicators still work normally.

I went to the local chevy dealer and bought the ambient temp sensor but can't find the harness end to plug it in. From a diagram I got from the dealer it looks like it should be hanging off the harness piece that plugs into something on the top driverside of the fan shroud. I've followed it as far as I can but can't see the temperature sensor connector anywhere.

Anybody have any suggestions? Am I looking in the right place or did the harness piece I need get moved or removed? FWIW I have the CJ3 manual climate controls and no fog lights (yet)