3FE no Spark getting CEL Code 12 anyone near Portland OREGON??

[36deucecruiser]

Have a 91 FJ80 been driving it daily for the last 8 months without a hitch, this past weekend parked it after a short drive and went to start it back up and it wouldn't start. The motor cranks over fine, but no spark. I pull the check engine codes with the paperclip trick and get code "12" after we towed it home.

Anyone have good suggestions, things to check or replace first to solve the problem?

I'm in beaverton Oregon, if there are any locals feel free to zap me an email or PM, this is my daily driver!

 

[pnwadventurer]

Do you have the manual that lists the diagnostic codes? If not, I have mine for a 92. Don't know if they are the same but should be. Let me know.

Steve

 

[TampaTom]

won't start?

I've had my 92 fail to start as if the ignition has been disabled. It has been the EFI relay. I have to replace it about every 2 years. I think that the wireing in general in my 92 was not heavy enough gauge to carry current through out the vehicle especially as it ages and resistance increases. That relay gets super hot.

 

[36deucecruiser]

Is there a way to test if the EFI relay is good? can you do a continuity test on it with voltmeter?

 

[Land Speeder]

easiest way to test your EFI relay is to go buy one from a parts store, usually around 10 bucks. Then if it works you need to address the issue of an overheating relay...

 

[36deucecruiser]

I took a picture of the Relay in the fuse box labeled "EFI MAIN"

Is this the EFI relay you guys are talking about?

 

[Lka1988]

Yup, that be the one.

I've had a few issues with mine, I just keep a spare in the glovebox.

 

[36deucecruiser]

Nope that not be the one, I just swapped that relay out for another one from my 91 LS400 and same thing cranks over, but no spark

I looked up in the chilton's book and it said code 12 is "distributor circuit", distributor, ecm

Has anyone else had a code 12 and no spark?

I pulled the distributor cap off and looked inside, does anyone know what i should look for?

thanks for all the replies, your guys expertise is much appreciated!

 

[Lka1988]

Nope that not be the one, I just swapped that relay out for another one from my 91 LS400 and same thing cranks over, but no spark

I looked up in the chilton's book and it said code 12 is "distributor circuit", distributor, ecm

Has anyone else had a code 12 and no spark?

I pulled the distributor cap off and looked inside, does anyone know what i should look for?

thanks for all the replies, your guys expertise is much appreciated!

Really? Well, that is the EFI relay... Not the culprit, then?

Check the wire running between the igniter and distributor, it may be loose.

 

[jonheld]

The motor cranks over fine, but no spark.

Did you search on this topic? I have written the diagnostic flow chart several times.

 

[36deucecruiser]

I've tried searching without sucess.. what should i put in the search fields to find your posting?

 

[jonheld]

I'm in the process of updating my website with this information. If we all live long enough it will be available for all...Keep in mind this is just a partial list and only deals with the lack of CEL (check engine light). Your problem could be igniter/coil related. Also note that the schematics can be downloaded from my web site in PDF format.

Here's a cut and paste from my Word doc....

Diagnostic Procedure for EFI Related Woe and Strife

The EFI circuit feeds +12 to the ECU, all 3 VSV valves, both O2 sensors, the ISC valve, and the load side of the circuit opening relay which feeds the fuel pump when the motor is running.

1. Motor not running; key in ON position; CEL should be on.
2. Check for +12 VDC on brass terminal screw in under hood fuse box. This terminal is located directly to the left of the main fuse and is a Phillips screw head. http://mysite.verizon.net/jonheld/images/OBA/Fusebox.jpg
3. If no +12 VDC in fuse box, then check fusible links off positive battery terminal. http://mysite.verizon.net/jonheld/images/EFIrelay/PosTerm1.jpg. While the one in the picture is not stock, the links are going to the stock locations. 2 to the black plastic junction box and one to the connector.
4. If +12 VDC in fuse box and no CEL, then suspect EFI relay/fuse and associated wiring and contacts. Many have said that the wire from the EFI fuse to the EFI relay is undersized and is the root cause of all these problems. I disagree with this. At idle I measured less than 1 amp across the load side of the EFI relay contacts. I believe the cause of the problems is related to the heat of the manifold combined with poor crimps on the connectors in the fuse box. Over time these connectors can become corroded and cause problems.
5. Check for +12 on pin 8 (B+) on the CHECK CONNECTOR mounted on the right side of the fire wall. If +12 on pin 8 and still no CEL, then EFI circuit OK and problem is with ECU or associated harness.

 

[jonheld]

Oh, and another thing. In your posts you said "no spark". Did you physically check for spark at the coil or are you making an assumption because the truck won't fire?

Pay particular attention to step #1 in my post above.

"1. Motor not running; key in ON position; CEL should be on."

If your CEL is on then the EFI circuit is functioning correctly and the problem is elsewhere.

When was the last time the cap and rotor were changed?

 

[FrankTorres]

I pull the check engine codes with the paperclip trick and get code "12" after we towed it home.

Anyone have good suggestions, things to check or replace first to solve the problem?

EFI relay's do not throw codes...if you are checking code your EFI circuit is fine.

Code 12 Diagnosis is (as per FSM), "no NE or G signal to the ECU within 2 seconds after engine has been cranked."

Trouble area (as per FSM). Distributor circuit, Distributor, Start signal circuit, and ECU.

Check all your connectors and wiring harness for corrosion and damage this includes the coil wire going to the distributor cap.
Then with a voltmeter check for voltage at ignition coil at the positive (+) terminal with the ignition key switched to ON.
Then take the cap of the distributor and do a visual check, is the rotor intact, is there water or oil inside? The FSM goes into detail on how to test the distributor.
Then if all else fails, there is the igniter, swap in a known good igniter from a fellow cruiser head that is willing to help and see if the beast starts.

good luck

 

[36deucecruiser]

Is there anyone local around here PDX area, that could offer a coil test swap?

 

[FrankTorres]

I wonder if a igniter from a 93+ would work?
OR any other Toyota just for the test?

This is an expensive part from the dealer

 

[jonheld]

www.cruiserparts.net

 

[jamesl Leritz]

I'm in the process of updating my website with this information. If we all live long enough it will be available for all...Keep in mind this is just a partial list and only deals with the lack of CEL (check engine light). Your problem could be igniter/coil related. Also note that the schematics can be downloaded from my web site in PDF format.

Here's a cut and paste from my Word doc....

Diagnostic Procedure for EFI Related Woe and Strife

The EFI circuit feeds +12 to the ECU, all 3 VSV valves, both O2 sensors, the ISC valve, and the load side of the circuit opening relay which feeds the fuel pump when the motor is running.

1. Motor not running; key in ON position; CEL should be on.
2. Check for +12 VDC on brass terminal screw in under hood fuse box. This terminal is located directly to the left of the main fuse and is a Phillips screw head. http://mysite.verizon.net/jonheld/images/OBA/Fusebox.jpg
3. If no +12 VDC in fuse box, then check fusible links off positive battery terminal. http://mysite.verizon.net/jonheld/images/EFIrelay/PosTerm1.jpg. While the one in the picture is not stock, the links are going to the stock locations. 2 to the black plastic junction box and one to the connector.
4. If +12 VDC in fuse box and no CEL, then suspect EFI relay/fuse and associated wiring and contacts. Many have said that the wire from the EFI fuse to the EFI relay is undersized and is the root cause of all these problems. I disagree with this. At idle I measured less than 1 amp across the load side of the EFI relay contacts. I believe the cause of the problems is related to the heat of the manifold combined with poor crimps on the connectors in the fuse box. Over time these connectors can become corroded and cause problems.
5. Check for +12 on pin 8 (B+) on the CHECK CONNECTOR mounted on the right side of the fire wall. If +12 on pin 8 and still no CEL, then EFI circuit OK and problem is with ECU or associated harness.

I seem to be at step 5. I have +12v at the +b pin in the diagnostic box. I have an 88 j62. still no spark and no cel what now??? please help I'm desperate.

Jay