95 Q TCS/ABS Issues - Advice Please?

[jamesmost]

OK tcs and abs disable soon afer take off. Tcs when working seems to only work if i powerbrake.ABS computer throws all different codes, Its confusedreplaced:relayscomputerrear wheel sensorsNoticed that the ABS Fluid is dark (burnt)\I have a replacment:Abs ActuatorTcs ActuatorTcs PumpWhat to try first ??

[maxnix]

Have to get rid of that fluid!

Any Consult data?

[Q45tech]

The brake fluid turns dark from absorbing moisture turning acidic and EATING the BLACK rubber orings in mastercylinder and ABS/TCS.

Amber brake fluid is just oxidized and moisture ladden as opposed to brand new clear.

[jamesmost]

oh yeah new master brake cylinderwhy would brake res have clean fluid and abs amber??

[Q45tech]

Because you didn't flush the entire system every year..................the ABS and especially TCS require some electronic exercise to clear the old fluid totally.

The ABS opens up space to decrease pressure whereas the TCS has extra fluid to pump to the rear shutting off any flow to from mastercylinder.........a simple caliper bleed will not exchange all the fluid.

[jamesmost]

the system has been bled every year 2X per year since i bought the car in 1997, what kind od electric flush do u recommend?which of my assembled parts should i throw at the car first?

[Q45tech]

We use a BG Machine that pressurizes the master cylinder [and continuously refills it as it vacuums each cylinder]...................it uses 2 liters of new brake fluid.

You must cycle the ABS and TCS systems with ABS System Checker and Consult..................never done at dealers unless major components are replaced.example of machine:http://www.lovejoyautomotive.c...s.htm

BG makes machines to flush every component except AC.

[jamesmost]

gonna find someone local w/' machine. but witch part u think actuator pump or abs actuator??

[Q45tech]

TCS and ABS have an integrated ecu so what are the codes.........that will point the way.

[jamesmost]

it throws: rr wheel sensor lr wheel sensor 2ndary throttle position sensor

all of which i am sure it is not the problem

[Q45tech]

Under those conditions I would just swap the ABS/TCS ecu as a quick check, AFTER making sure there was no visable sensor cable/harness damage. 3 diverse sensor codes is unusal.

Secondary TPS is a common failure as is the secondary throttle motor.

[jamesmost]

Under those conditions I would just swap the ABS/TCS ecu as a quick check, AFTER making sure there was no visable sensor cable/harness damage. 3 diverse sensor codes is unusal.

Secondary TPS is a common failure as is the secondary throttle motor.

i swapped the computer and have same issues, bty per ur advise.

[Q45tech]

Then you observe the electronic signals from each sensor to make sure they match the FSM............make sure they are flowing into ABS/TCS ecu.........back probe the connector.

Same with secondary tps you read ohms and change position to make sure ohms track FSM ................read at ecu connector.

All these test proceedures are outlined in FSM.

[jamesmost]

uggh

[maxnix]

Good luck James. Looks like it is time for your first write-up.

[jamesmost]

waiting for some more parts, gonna throw some at the car and see if they stick. toooooooo cold to do anything now

[msogun]

I just changed my rotor and ABS-SLIP-TCS light comes up. Plus some noises are coming from the rear. Called the person who sold it to me and mentioned I should turn it before installing it. Here is the information about the rotor --------------------------------------------------------------------------------------------------------------------------------eBAY Item: 1 Premium Rotor Infiniti Q45 Rear 1990-96 (270036604369) ------------------------------------------------------------------------------------------

HERE IS THE EMAIL HE SENT TO ME. Hi At our shop when we install any new rotors we have them turned first to make sure that they are true. That may be what you need to do. Thanks Shawn

[maxnix]

Trueing any rotor before installation is a good idea.

Buying a rotor off eBay is not as it is at best a crapshoot. Genuine Brembo from TR is so cheap for starters.

[msogun]

My problem is solved. I turned the rotor and followed the instruction on page 7-18 and 7-19 in the owner's Manual. Try it. It works. No more SLIP, TCS and ABS lights.

[jamesmost]

My problem is solved. I turned the rotor and followed the instruction on page 7-18 and 7-19 in the owner's Manual. Try it. It works. No more SLIP, TCS and ABS lights.

what does it say to do ??

[msogun]

They asked you to press on the brake for several time. Then turn the car on and keep pressing for 1-2 minutes and then cut it off. Whait for few minutes and repeat the process. Then turn the car off for about 5 minutes. It should work. SLIP, ABS and TCS is a brake problem. So examine your brake, pad, and rotors.
Modified by msogun at 5:18 AM 3/6/2007

[maxnix]

Break or brake?

[msogun]

Should be brake.