Carboxy

Hi all,
My check engine light came up the other day. Where can I find information either webpage or manual that will help me diagnose the problem. The car is working fine, but the check engine light is freaking me out.
Maybe some knows what causes the engine to light up.
Rob

VQT

Does the trac light on also?

use a paper clip and stick in the T1 and TE1 of the little round thing under your dash above your left knee. You need to open the cap and use the paper clip to check the code. Turn the igntion on, do not start the engine. Count the no. of flashs including the pause. 34 mean 3 flashs pause the 4 flashs.

Post the code here someone with the manual will help.

If you want a manual, try one of the web site. Carson Toyota 800-908-6968 start charging me shipping now and their price wasn't that great to begin with. Their price is still much better than the dealer though.

Carboxy

VQT et al,
thanks for the fast reply. where can I find the t1 and te1 again is under the driver side?
also, can someone fax me a page the lexus manual on the flashes interpretation?

VQT:
I see that you have 93 sc400. What's your rpms @ 40, 60, and 80 mph?
Rob

fax: 352-392-4707

VQT

Read again what I wrote
It's the ALDL above your left knee under the dash. Look for a round piece with a cap covered. Didn't pay attention to rpm

methodmf

i been having this problem 4 a while now
the engine light disappears everytime i floor my car and comes back a few days later. disappears again next time i race

it's strange

VQT

You are talking about 200 pages of code interpretation...
It's better to get yourself a manual

Carboxy

VQT and all,
I brought my sc400 to a toyota dealership. they counted the light as 25, what does that mean?
R

VQT

How much did it cost you by the dealer to get that code?
Why don't you try it with what I told you. It should give you the same code without going to the dealer.
code 25 mean lean air/fuel mixture. How many miles on the car? What did you do lately that the engine light went on? washing the engine?

There are several thing to check with code 25. Do you have a ohm/volt meter? It could be the throttle position sensor (TPS), or the mass air flow sensor (MAF) or the Oxygen Sensors. SC400 has 4 O2 sensors. 2 main and two secondary. It could be one of your main O2 sensors. You need to know which one to replace. There is a way to check it, I don't have the manual here at work. Are you handy with tools? If not you're looking at $500 to change the main O2 from the dealer, if it turn out to be the problem.
I bought my O2 sensors at $250 for both. That's not dealer price. Some member bought Borsh O2 sensor from Autozone or the like for $35 each.

Don't go and change O2 sensors until you know exactly what's wrong.

VQT

call 800-908-6968 ask for Steve Ganz. tell him you are a forum member. He should have the repair manual at a cheaper price than the dealer. Also ask him about shipping charge. Should not charge shipping.

Carboxy

VQT,
I brought it to toyota and they checked it. They suggest it might be the o2,but wanted to me to bring to a Lexus dealer to run a diagnostic. I have some friend who are quite handy with tools. I do have a ohm/vol meter.
Just give me so directions and I will try it
here's my # 352-219-0328 give me call anythime
Rob
ps
the engine light turn off this morning b4 i brought it to toyota.

SupraCoup3

The way I get rid of that light on my 93 SC400 (happened during a snow storm, and needed traction control -- emergency!) is to open up the fuse box in the engine compartment, and to pull the EFI fuse, it's the first 30A (amp) fuse from the top working down.

Pull that fuse, then put it right back in. The Check engine & Trac Off light immidately goes away.

Taka

I have ordered repair manual from steve/gordon,plus other parts last month. but I haven't received them yet since they needed to order repair manual, it took a month. should be here today or tommorow. shipping fee, $12.
I'll work on my side mirror ECU during new year.
Wish me luck, VQT.

The Ikon

My check engine and trac light came on after a hard left turn at an intersection... I simply turn the car off disconnect the battery and presto it has not happened again...

The first time this happed I was 2 quarts low on oil after I just got an oil change!!! NOTE always double check your oil level before you leave the shop!!!

VQT

There is a lot more to this test that I can’t type in because it involve looking up different page of the manual. It is recommend that you buy the book. Then when you don’t understanding what the book read ask forum member. Hopefully someone with knowledge will try to answer it. I am not a mechanic. I just read drom the book and troubleshoot the problem myself.

DIAG. TROUBLE CODE 25/26 FOR 93 SC400

There is a DLC1 under the hood. It’s a small black box with a cap covered located at the front left of the engine.
1. Warm up the engine to normal operating temperature
2. Connect terminal TE1 and E1 with a paper clip.
3. With a voltmeter, connect positive probe to terminal VF1, VF2 and negative probe to terminal E1 of the DLC1. Probe VF1 and E1 then VF2 and E1.
4. Warm up the oxygen sensor by running engine at 2,500 rpm for about 2 minutes.
5. Then, maintain engine at 2,500 rpm, count how many times needle of volt meter fluctuates between 0 and 5 V.
Results
Needle fluctuates 8 times OK
Continue at 0 V NG type I
Continue at 5V NG type II

Check Voltage between terminals OX1, OX2 and E1 of DLC1.

NG type I
1. Engine still at normal operating temperature.
2. Measure voltage between terminal OX1, OX2 and E1 of DLC1 when engine suddenly race to full throttle.
3. The voltage should be 0.5 V or higher at least once----OK
Need to perform this inspection within 1 sec.

NG type II

There are too much in formation to type in here. Need the whole repair manual.

There is another check for oxygen sensor

1. Start engine and warm up
2. After engine is warm up, let it idle for 3 min.
3. With A/C ON and trans. In D position (O/D ON) perform gradual acceleration within the range 1,300-1,700 rpm (centered around 1,500 rpm)
(Take care that the engine speed does not fall below 1,200 rpm when shifting. Gradually depress the accelerator pedal and kept it steady so that engine breaking does not occur.)
4. Maintain the vehicle speed at 40-50 mph (64-80 km/h)
5. keep the vehicle running for 1-2 min. after starting acceration.

HINT: If a malfunction exists, the malfunction indicator lamp will light up after approximately 60 sec. from start of acceleration.

NOTICE: If the conditions in this test are not strictly follow. Detection of malfunction will not be possible.

VQT

When I ordered mine, it took a month also...
Take the negative post of the battery out so you don't have my problem. The power mirror ECU is PITA to take out. Just take your time