reading codes

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Joined
Jan 6, 2007
Threads
6
Messages
35
1988 toyota V6 pickup

I need to read my codes. I know where to jump, I've done it before but this time I get no response.
The computer has a code while running but when I shut it off and jump the terminals, the check engine light doesn't blink- it just stays light. What could be the problem?
 
unless the diagnostic portion of the ECU is comprimised, you must have a bad connection.
try this, remove the plastic wire cover under the DLC port. and push up on the wires to make sure the are all the way up.

over the years, my trucks wires have been pused down so far that i couldnt get a reading.
 
OUTPUT OF DIAGNOSIS CODES
To obtain an output of diagnostic codes, proceed as follows:

Initial conditions
(a) Battery voltage above 11 volts
(b) Throttle valve fully closed (throttle position sensor IDL points closed)
(c) Transmission in neutral position
(d) Accessory switches OFF

Turn the ignition switch to ON. Do not start the engine.
Short terminals T and E1 of the check connector . NOTE: The check connector is located near the No.2 relay block.


Read the diagnosis code as indicated by the number of flashes of the "CHECK ENGINE" warning light.
System Normal

Diagnosis code


(a) Normal System Operation
The light will blink once every 0.25 seconds.

System Malfunction


(b) Malfunction Code Indication
The light will blink a number of times equal to the malfunction code indication as follows:

Between the first digit and second digit, 1.5 seconds.
Between code and code 2.5 seconds.
Between all malfunction codes 4.5 seconds. The diagnostic code series will be repeated as long as the check connector terminals T and E1 are shorted. NOTE: In event of a number of trouble codes, indication will begin from the small value and continue to the larger in order.
After the diagnosis check, unshort the check connector.
 
Turn the ignition switch to ON. Do not start the engine.
Short terminals T and E1 of the check connector.

On GM at least, if you short the terminals before turning the ignition on you enter a "calibration" mode instead of the "read codes" mode. Don't know if it matters on an '88 mini.
 
On GM at least, if you short the terminals before turning the ignition on you enter a "calibration" mode instead of the "read codes" mode. Don't know if it matters on an '88 mini.

not in any way is this posible on a yota. if you read the post above yours it further explains tho how and the tao.
 
OUTPUT OF DIAGNOSIS CODES
To obtain an output of diagnostic codes, proceed as follows:

Initial conditions
(a) Battery voltage above 11 volts
(b) Throttle valve fully closed (throttle position sensor IDL points closed)
(c) Transmission in neutral position
(d) Accessory switches OFF

Turn the ignition switch to ON. Do not start the engine.
Short terminals T and E1 of the check connector . NOTE: The check connector is located near the No.2 relay block.


Read the diagnosis code as indicated by the number of flashes of the "CHECK ENGINE" warning light.
System Normal

Diagnosis code


(a) Normal System Operation
The light will blink once every 0.25 seconds.

System Malfunction


(b) Malfunction Code Indication
The light will blink a number of times equal to the malfunction code indication as follows:

Between the first digit and second digit, 1.5 seconds.
Between code and code 2.5 seconds.
Between all malfunction codes 4.5 seconds. The diagnostic code series will be repeated as long as the check connector terminals T and E1 are shorted. NOTE: In event of a number of trouble codes, indication will begin from the small value and continue to the larger in order.
After the diagnosis check, unshort the check connector.

Wow,that was just like reading the book, lol. Do you have mitchel ondemand or something?

I need to know why I can't get codes providing I've done everything above.... The light does not flash, it just stays on as if the jumper wire is not there. I've tried pushing up on the wires but I can't get it to read. I've done it before so I know what to do but...
 
it could be a bad ecu. the newer toys have a wire you have to disconect first. is your jumper on the drivers fender or the passenger fender\firewall? the one on the passenger side has another conector within about six inches that has to be disconected.
 
it could be a bad ecu. the newer toys have a wire you have to disconect first. is your jumper on the drivers fender or the passenger fender\firewall? the one on the passenger side has another conector within about six inches that has to be disconected.

I've been using the one on the passenger side. I didn't notice any other connector but I'll take a look and give it a try. Last time I read codes I didn't mess with the connector and it read code fine...
 
s the cel always on or does it take a while to set the light?

I figured it out... I think.
I can't read codes because there arnt any there...
I think the spark advance was so retarded that it wasnt running correctly. I advanced the distributor and the truck moves out pretty well now... the engine light doesn't come on until I floor the throttle now. The timing may still be off. I think the timing tool I was using may be off... (its one of those old analog scales)
I have to find a gun from somewhere to check it further.
I still get that friggin pulsation when I step on the brake pedle though... arggg!!!
 
If there are no codes in the ECU then when you jump the terminals the CEL will just flash at a constant rate....

Does the truck "pulsate" when you hit the brakes, or is it the engine?

The light doesn't flash. It stays on constant...
The engine pulsates but only when the break is applied. It's REAL annoying at stop lights!
 
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