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Nov 29, 2014 | 01:16 PM

Rickbean

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Joined: Nov 2014

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From: Virginia

Check engine light

Does anyone know how I can figure out why my engine light is on. I have a 95 sc300 I took it to the auto zone and the guy told me they can't hook it up To a computer? Any suggestions will be appreciated

Nov 29, 2014 | 01:39 PM

scENFORCER

Pole Position

Joined: Oct 2006

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From: BC

Take it to a real mechanic.

Nov 29, 2014 | 01:52 PM

tfwnoturbo

Pit Crew

Joined: Nov 2014

Posts: 178

Likes: 20

From: North Carolina

Quote:

Originally Posted by Rickbean

You seriously took it to Auto Zone as your first choice?

As enforcer said, take it to a dedicated shop, not to the walmart of Auto Parts.
That or use your own code scanner to figure out the code.

Nov 29, 2014 | 02:10 PM

t2d2

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Geez fellas, take it easy on the new guy. Some Auto Zones, like the two nearest me, are filled with very knowledgeable car guys. Obviously, that's not true everywhere, but the OP's decision to go there first isn't necessarily a bad one just because your experiences have been poor. Everyone's had a bad mechanic at some point, but I don't hear anyone saying to avoid mechanics altogether as a result.

Nov 29, 2014 | 02:28 PM

Black1UZ

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From: NC

Or you can buy a little scanner for less than 30 bucks that spots the codes and you can look them up. Save yourself money and time

Nov 29, 2014 | 03:08 PM

FastTags

Lexus Test Driver

Joined: May 2014

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From: tx

OBD2 works on 1996 and up vehicles. Cars before 1996 did not have a slot, the only way is to hook it up directly to computer which some mechanic shop will have but not the Autozone

Nov 29, 2014 | 03:55 PM

t2d2

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Quote:

Originally Posted by FastTags

OBD2 works on 1996 and up vehicles. Cars before 1996 did not have a slot, the only way is to hook it up directly to computer which some mechanic shop will have but not the Autozone

Or the other "only way" of jumpering the engine diagnostic port pins with a paperclip.

jumper E1 & TE1, then turn ignition to "On" and count CEL flashes.
e.g. code 71 (egr) = 7 blinks, pause, 1 blink, long pause, repeat.

OBDI Trouble Codes:
12/13 RPM Signal
14/15 Ignition Signal
16 Electronically Controlled Transmission Control Signal
17/18 CMP #1/2
21 Main O2S & Heater Signal
22 ECT Sensor Signal
24 IAT Sensor Signal
25 Air-Fuel Ratio Lean Malfunction
26 Air-Fuel Ratio Rich Malfunction
27 Sub O2S Signal
28 Main O2S
29 Sub O2S
31/32 Air Flow Meter Signal
35 HAC/Barometric Pressure Sensor Signal
41 TP Sensor Signal
42 VSS Signal
43 Starter Signal
47 Sub TP Sensor
48 Secondary Injection System Malfunction
51 Switch Condition Signal
52/55 Knock Senosor (KS) #1/2 Signal
53 Knock Control Signal
70/71 EGR System Malfunction
78 Fuel Pump Control

The constant blinking of the check engine and O/D means it hasnt thrown any codes.

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Dec 2, 2014 | 11:40 PM

Twojaybee

Driver School Candidate

Joined: Nov 2014

Posts: 5

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From: Wa

I know it says ls400 but follow the procedure, has pictures too.
Worked on my 93 sc300. Super easy, just gotta pay attention to the CEL when it blinks. I got this bookmarked just in case mines ever decides to show up again. Click the link or copy n paste it in a new window for easy instructions with pics!!

http://www.lexls.com/tutorials/intro/codereading.html

You're welcome!!

Dec 4, 2014 | 09:02 PM

#10

salimshah

CL Community Team

Joined: Apr 2001

Posts: 16,560

Likes: 1,385

From: Austin, TX

Any suggestions on how to read CEL that comes on and then goes away? By the time I get home the CEL is off. One option is it ignore it till the light comes on and stays on.

OBDII has pending codes, is there some thing like Pending Codes with OBDI?

Vehicle is 95 SC400

Salim