1993 Gs300 Trac Light On - Need Trouble Code Help

[the.batman]

This pertains to 1993 GS300. After a snow storm and lots of Traction Control activation, the amber TRAC light now comes on after about 5 minutes of driving, and stays on (dry roads). I read the similar thread for a 1994 GS300, and I followed the instructions on diagnosing the problem. The brake fluid reservoir was pretty much full, but I added more and drove it and the TRAC light still comes on, so I figure that can't be the problem.

Next, I pulled the "Short Pin" in DL1 (under hood). I put a jumper between Tc and E1 of DCL2 (under steering wheel). Turned ignition to ON and the following lights flashed.

The little red "airbag picture" warning light flashed ON/OFF constantly. The red "Cruise" warning light flashed ON/OFF constantly. The amber "ABS" warning light flashed 5 times.. pause.. 4 times. The amber "TRAC" warning light flashed 4 times.. pause.. 3 times.

I'm confused on what this means as the ABS Diagnostic Trouble Code Chart that I found on Lexus Forums didn't have that combination of lights for both the ABS light and the TRAC light.

I should add that I turned the Traction Control system off (dash button) and the TRAC light still comes on after about 5 minutes of driving.

Can anyone advise on what I need to check/replace next?

Thanks for any help on this.

[GuyTelefunken]

Seems like the flow chart is pointing to the accumulator. This would be the canister that holds the pressurized brake fluid until it is needed by the brake system. They can leak internally allowing the pressure to bleed down in a short time, in turn, causing the pump to run too often.

[Jasom Parrott]

Seems like the flow chart is pointing to the accumulator. This would be the canister that holds the pressurized brake fluid until it is needed by the brake system. They can leak internally allowing the pressure to bleed down in a short time, in turn, causing the pump to run too often.

I'm having the exact same symptoms with my '95 GS300. Is it possible to just disconnect the TRAC system and still operate the car safely? I have no idea how to replace the accumulator.

[305pimpc]

Seems like the flow chart is pointing to the accumulator. This would be the canister that holds the pressurized brake fluid until it is needed by the brake system. They can leak internally allowing the pressure to bleed down in a short time, in turn, causing the pump to run too often.

I'm having the exact same symptoms with my '95 GS300. Is it possible to just disconnect the TRAC system and still operate the car safely? I have no idea how to replace the accumulator.

I hope this helps out for you guys with the frist gen gs300! it hard to get help around here!!!

Engine OBDI Diagnostic Codes

The list below will tell you where the problem lies but will not go into diagnosis. Please consult your repair manual for in depth diagnosis, testing and troubleshooting.

12 - RPM signal no. 1

13 - RPM signal no. 2

14 - Ignition no. 1 signal

15 - Ignition no. 2 signal

16 - ECT control signal

17 - No. 1 cam position sensor signal

18 - No. 2 cam position sensor signal

21 - Main oxygen sensor signal (on left bank)

22 - Water temp sensor signal

24 - Intake air temp. sensor signal

25 - Air-fuel ratio lean malfunction

26 - Air-fuel ratio rich malfunction

27 - Sub-oxygen sensor signal (on left bank)

28 - Main oxygen sensor signal (on right bank)

29 - Sub-oxygen sensor signal (on right bank)

31 - Air flow meter signal

35 - HAC sensor signal

41 - Throttle position sensor signal

43 - Starter signal

47 - Sub-throttle position sensor signal

51 - Switch condition signal

52 - No. 1 knock sensor signal

53 - Knock control signal

55 - No. 2 knock sensor signal

71 - EGR system malfunction

Transmission OBDI Diagnostic Codes

42 - No. 1 speed sensor signal malfunction

46 - Open or short circuit in no. 4 solenoid valve

61 - No. 2 speed sensor signal malfunction

62 - Open or short circuit in no. 1 solenoid valve

63 - Open or short circuit in no. 2 solenoid valve

64 - Open or short circuit in no. 3 solenoid valve

67 - OD direct clutch speed sensor signal malfunction

68 - Short circuit in kick-down switch

Air Bag OBDI Diagnostic Codes

11 - Short in squib circuit or front airbag sensor circuit (to ground)

12 - Short in squib circuit or front airbag sensor circuit (to +B)

13 - Short in squib circuit (between D+ wire harness and D- wire harness)

14 - Open in squib circuit

15 - Open in front airbag sensor sensor circuit

22 - Airbag warning light system

31 - Center airbag sensor assembly malfunction

41 - Malfunction stored in memory

ABS OBDI Diagnostic Codes

11 - Open circuit in ABS solenoid relay circuit

12 - Short circuit in ABS solenoid relay circuit

13 - Open circuit in pump motor relay circuit

14 - Short circuit in pump motor relay circuit

21 - Open or short circuit in 3-position solenoid circuit for front right wheel

22 - Open or short circuit in 3-position solenoid circuit for front left wheel

23 - Open or short circuit in 3-position solenoid circuit for rear right wheel

24 - Open or short circuit in 3-position solenoid circuit for rear left wheel

31 - Front right wheel speed sensor signal malfunction

32 - Front left wheel speed sensor signal malfunction

33 - Rear right wheel speed sensor signal malfunction

34 - Rear left wheel speed sensor signal malfunction

35 - Open circuit in front left or rear right speed sensor circuit

36 - Open circuit in front right or rear left speed sensor circuit

37 - Faulty front speed sensor rotor

41 - Low battery voltage or abnormally high battery voltage

43 - Malfunction in TRAC control system

51 - Pump motor is locked, Open in pump motor ground

Always ON - Malfunction in ECU

TRAC OBDI Diagnostic Codes

11 - Open in TRAC brake main relay circuit

12 - Short in TRAC brake main relay circuit

13 - Open in TRAC throttle relay circuit

14 - Short in TRAC throttle relay circuit

15 - Electric supply to TRAC motor for a long time (fluid leakage)

16 - Open circuit in pressure switch circuit

17 - Pressure switch remains OFF

19 - TRAC motor ON and OFF operation is higher than a predetermined number of times (accumulator pressure leakage)

21 - Open or short in master cylinder cut solenoid valve circuit

22 - Open or short in accumulator cut solenoid valve circuit

23 - Open or short in reservoir cut solenoid valve circuit

24 - Open or short in sub-throttle actuator circuit

25 - Step motor does not move to a position decided by ECU

26 - Sub-throttle valve does not move even when the sub-throttle valve is controlled to fully open position by ECU

27 - When power supply to step motor is stopped, sub-throttle valve does not reach its fully-open position

44 - During TRAC control, NE signals are not input to the ECU

45 - When idle switch is ON, main throttle position sensor signal is 1.5V or higher

46 - Main throttle position sensor signal is 4.3V or higher, or main throttle position sensor signal is 0.2V or lower when idle switch is OFF

47 - When idle switch is ON, sub-throttle position sensor signal is 1.45V or higher

48 - Sub-throttle position sensor signal is 4.3V or higher, or sub-throttle position sensor signal is 0.2V or lower when idle switch is OFF

49 - Open or short in engine communication circuit

51 - Problem in engine control system

52 - Brake fluid level warning switch ON

54 - Open in TRAC motor relay circuit

55 - Short in TRAC motor relay circuit

56 - TRAC pump motor locked

Always ON - Malfunction in ECU

[sakataj]

I hope this helps out for you guys with the frist gen gs300! it hard to get help around here!!!

nice post.... :) your right somedays it can be VERY hard to get help around here as some of the OG's act like they to good to post on some peoples topics and no not just mine. i decided to give up on it, i post to help people so i still stick around but as you can tell from my other posts, i have really moved on to a more helpful place. but again very nice post. i left out all the details so i didnt clog this post