Damn.. no test cars?

 

Apparently the CEL light should not come on though a code will be issued and the car may enter "fail safe" mode. Kevin's module will work best as it won't pose a safety hazard that a simple toggle switch would as the cruise won't disengage either when you brake if you have a manual switch in there:

DTC P1805 BRAKE SWITCH PFP:25320
Description ABS003JR
Brake switch signal is applied to the ECM through the stop lamp switch when the brake pedal is depressed.
This signal is used mainly to decrease the engine speed when the vehicle is driving.
CONSULT-II Reference Value in Data Monitor Mode ABS003JS
Specification data are reference values.
On Board Diagnosis Logic ABS003JT
The MIL will not light up for this diagnosis.
FAIL-SAFE MODE
When the malfunction is detected, the ECM enters fail-safe mode.
DTC Confirmation Procedure ABS003JU
WITH CONSULT-II
1. Turn ignition switch ON.
2. Fully depress the brake pedal for at least 5 seconds.
3. Erase the DTC with CONSULT-II.
4. Select “DATA MONITOR” mode with CONSULT-II.
5. If 1st trip DTC is detected, go to EC-538, "Diagnostic Procedure"
.
WITH GST
Follow the procedure “WITH CONSULT-II” above.
MONITOR ITEM CONDITION SPECIFICATION
BRAKE SW
Ignition switch: ON
Brake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1805
1805
Brake switch
A brake switch signal is not sent to ECM for an
extremely long time while the vehicle is driving.

Harness or connectors
(Stop lamp switch circuit is open or
shorted.)

Stop lamp switch
Engine operating condition in fail-safe mode
ECM controls the electric throttle control actuator by regulating the throttle opening to a small range.
Therefore, acceleration will be poor.
Vehicle condition Driving condition
When engine is idling Normal
When accelerating Poor acceleration
SEF058Y

 

Need a test car??

 

Run into problems with it? I'd love to get my hands on something like this as long as it worked properly without adverse side effects (no speedo, etc). Updates?

 

Kevin,

Would this thing do basically the same thing as what you are designing? There'd be no way to tie it into the VDC, but other than that (so it would be active all the time)...

http://www.caraudio-caralarms.com/528T.html

I'm just wondering why would you need to ever turn it off? That is, when you press the break, the ECU gets a pulse rather than a continuous feed from the brake switch. Any harm in that?

EDIT: I just ordered one off ebay - will let you know if it works... (though I am NOT boosted so can't test that too well - what I can test is a brake torque launching)

 

I didn't run in to any problems with it, its done and just sitting there.

RCDash, that should work. My only concern with it would be the fact that it uses a mechanical relay on the brake wire that will pulse every time you hit the brake pedal. However, since this is not a critical circuit if it were to fail (typically relay is rated for 100,000 or so cycles) it really wouldn't be a big deal. You may also want to think about mounting locations, as you may actually hear it click every time you hit the brake pedal. A little insulation and some creative thinking can fix that too, if it is a problem.

I'm not sure if there would ever be a reason to not bypass the system.

 

it was $16 bucks shipped on ebay; so i said what the heck. i have another project i can use it for if this is a no-go.

good point on the mechanical relay - didn't know it was using a mechanical one actually. I will add an indicator LED so that I can easily tell if it's working (if it doesn't have one).

or maybe i'll know cause the clicking will stop! actually i figure I press the brake maybe 10-20 times a day (gotta like living in NC!) at most. that's what 5000 days or about 12+ years worth of use if it lasts for 100k cycles?

btw, if you're going to integrate this into your VDC module then i'd still be up for that... let me know cause i have a carPC project I can use this other relay for instead...

 

Anyone get this done? I'd like to see some vids!!

 

+1

 

I've actually got my car back together, so maybe I'll try it out this weekend.

 

No boost here yet... But would this stop the bogging that I get when I brake torque launch my 5AT? When I stand on the brake and pree the gas the car wont launch hard at all. I can feel the power come back strong maybe a second after I let off the brake when launching. I think the ECU is closing the throttle becasue of the brake and gas being pressed at the same time. I also cant do good burd outs

 

On the highway today I played around with the brake and the gas and found that if I press the brake I can not rev higher then the current RPM.

 

Was this with the unit installed that was talked about earlier in this thread ? And did it build any boost ?

 

Hi phunk it has been a while... the drag starts soon and i was looking and just reading and i saw our post if u go back to page 1 any way i just wanted to tell u no it doesnt work i tryed the line lock my self and it doesn't work the problem is the abs will unleash the line lock so to be able to do it i need to take the abs fuse off i haven't tried that 1 but i will and i will let u know...

 

No, that was stock.

I made a comment earlier in the thread about not knowing if my G35 did the same thing as the 350Z. It does, in fact, do the same thing. This makes it a perfect canidate to be the test mule!

 

I still want to test your unit, any interest on your end?

 

Yes, there is interest, but I prefer to do initial testing on my own car. Once I get that done, we can move forward with a field beta test.

 

Any kind of time bracket when you plan on doing some testing ? Spring is on the way and doing some brake boosting would be fun .

 

Spring may be on the way, but there is snow on the ground here in Ohio.

I was planning on installing it today, but my garage was way too cold. I barely got my fuel pressure sending unit installed. I couldn't find the motivation to install this module as I knew I wouldn't even be able to test it.

It's supposed to warm up this week, so hopefully I'll get it in by the weekend. I also have some new spark plugs that are supposed to be here tomorrow. Should be a busy week.

 

just remove the fuse on the bottom left side of the drivers seat. Its the break lamp fuse. Thats all u have to do