gxman1

Question where is the Skid Control ECU is located. I dont have the shop manual. I am going off your PDF file to test the voltage.

Thanks

RCsGX

See attached.

RCsGX

Added one more PDF above....

gxman1

Thank you, will look at near the fuse box 2, I wish I had the Manual PDF for 2004 Lexus. By the way do you have a diagram underneath the H L N, I am thinking the switch underneath is loose, and it is not sending the signal it is in L position.

RCsGX

I can't find any upclose pages. I'm attaching all I could find regarding DAC.

If you need any wiring schematics let me know and I'll see what I can find.

mann777

Just want to know are you depressing the brake pedal while the system gets activated, or have I missed what you are trying to do.

gxman1

Good question? Here is what I am doing at the moment, and it may seem I am doing it incorrectly after reading DAC Pdf file from RC'a post.

I am in the driveway, and pressing the switch and it blinks, I have to apply the brake to do it. I think it is cancelling the DAC and it is blinking.

Anyone reading this, try this when you are parked, car started, shifter in N and the H N L to L, and than shifter to D position, afterwards press DAC switch. The switch should blink and did it turn solid?

The problem is if you do this in the driveway you have to press the brake.
If you do this on a flat street without pressing gas or break, it still flashes.
At the moment I cant find a hilly area to try it.

Please let me know, can you looked at the attached file, it was sent from RC, I made comments on it in RED dotted and solid boxed.

RCsGX

I just tried and it does light up solid. Here's what I did.

• Foot on the brake
• Started the GX
• Transmission in N
• Transfer case in L
• Transmission in D
• Pressed the DAC switch, it immediately lit up solid no blinking what so ever
• Removed foot from the brake
• DAC engaged and slowly took me down my driveway

The DAC will cancel once you're using it if you hit the brake, just like cruise control.


EDIT:
Sewell transfer case indicator switch, also see attached PDF.
http://lexus.sewellparts.com/oem-cat...X470-2005.html

gxman1

RC,

Cant thank you enough. I really appreciate you doing this. I just came back from testing myself, I took it off road decline and would not work, tried it with no brakes at all and other variants, including the one you wrote.

I have a question, how fast the truck was going when DAC started to brake for you? What speed was it maintaining?

RCsGX

Not a problem.

The DAC kicked in within 1-2 seconds after i let my foot off of the brake and I was probably going 1-2MPH if that? The speedo needle barely moved past 0 and was not even midway between 0-5MPH. Worked the same way in reverse too.

gxman1

RC, Mann777

Found the issue. Rc thanks for all the attachments I requested, it has helped. I found out it is a common problem with the switch, most GX owner rarely use the switch, so they arent aware of it.

If you recall from my earlier post, I attached a pdf with my writing on it asking for "where can I find the Transfer Indicator L4 Switch"? Well that was it, I didnt follow the troubleshoot and took a quick 2 minute diagnostic. Pictures are attached below. Without jacking the car I crawled underneath the car, found out it was very easy to remove the switch harness jumped it with paper clip, went inside the truck and no more flashing light!! Worked perfectly, jumping tricked the ECM indicating transfer case was in L position.

NOTICE IN 2ND PHOTO I UNPLUGGED IT AND PUT A PAPER CLIP.

The part is around $57 and the part # is SWITCH, TRANSFER IND - 84222-35080
There are 2 switches on the transfer case DRIVER SIDE and this is closest toward the engine, the plug color is DARK BLUE.

NOW THE QUESTION IS HOW DO I REMOVE THE ACTUAL SWITCH ANY INSTRUCTIONS?
I know I need 1 1/16 Crow feet wrench or 27MM it is a tight spot, I dont know if it open it.

It is easily seen when on your back but hard to get to, an instructions will be awesome.

keyword: DAC Downhill Assist Control Down Hill Assist Control Flashing blinking

mann777

You need to pry it out the trim panels on either side of the Gear Shifter first. These need to be done carefully with a some kinda putty knife and taped on the edges so that you don't damage the trim panels or the console. First Target the Left Side Panel Image 1 and then the Right Side. Only thing you need to be careful about is to disassembly of the center console. Start by removing the trim piece to the left of the shifter ****. . Insert a putty knife in the crack just in front of the parking brake lever and gently pry up. There are three clips under the trim piece that need to be pulled out of the console. It does take a lot of force to remove them.
Next you target the panel which is shrouding the DAC switches. Which would be visible ( clips ) to you from both sides ( view below to get an idea ). And pry them out.

I have a feeling you may have to pry the wood panel around the centre console and then reach down to the Coin Tray and the Cigarette Lighter part. But before you go there, you want to do the first part, that would save lot of time. Also the GX clips around the trims are pretty hard pressed, so need a extra bit of pressure to pry them out. Good luck let us know how it goes

mann777

Ok here is what I found from the manual, for the Flashing lights, So I assume after reading the DAC operation the switch flashing is not the part which is faulty. But Check out the manual what it says and the flashing reason. So before you do the switch replacement. I may be wrong here after you have done all the troubleshooting. But the flashing of the switch occurs for a reason as that what the manual says.

gxman1

The manual doesnt apply in this situation. It is not being used frequently. And when I jump the switch, all it did was send a signal the gear is in L, thats all. And the light was solid all working fine.

I have a question on the center console removal, do you think i can reach the bottom of truck from opening to open the 27 mm switch, since the actual switch is on the driver side on the top of transfer case underneath the truck. I think there may be not enough room to reach thru the hole. Just curious why you suggested this method instead of trying from the bottom.

Thanks

mann777

Ok you are talking of the L4 detection switch While I was talking of the DAC SW on the pedestal itself. But My question to you how did you determine which switch is faulty could be either one. Either the DAC switch on the pedestal or the one L4 Detection Switch. You may need to check the resistance to confirm the faulty one. Yes accessibility for the L4 is from below, but definetely cramped up leading to the ECM.