1996 Toyota Avalon MIL STATUS LIGHT

Tiny
SILVESTRIK
  • MEMBER
  • 1996 TOYOTA AVALON
  • 6 CYL
  • FWD
  • AUTOMATIC
  • 145,000 MILES
1996 Toyota Avalon
In order of events:
a. No light/nor error codes.
b. Replaced driver's side transaxle due to normal wearing.
c. Replaced transmission with a used one due to mechanic's error by not correctly seating axle seal and burned out original transmission.
d. Two error codes appear after tranny swap.
1. Rear O2 sensor 2. Transmission clutch speed sensor.
e. Replaced O2 sensor and removed code. Repaired bad 2 wire connector on speed sensor and removed code.
f. MIL light remained on. Unable to clear it, despite attempts from 3 garages.
g. Had emissions shop diagnose the problem. Says it must be the ECU and wanted $1800 to replace it, with no guarantee it will solve the problem.
h. I purchased a new old stock ECU off Ebay and installed it in the car. No change in MIL status light.
i. ECU is not flash programmable and is the exact model for this car.
j. MA inspection extension expires in 5 days. This is my son's college commuting car and we will be forced to take it off the road.
k. Other than this light, everything works great on this car.

PLEASE HELP!
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Thursday, November 19th, 2009 AT 2:32 PM

15 Replies

Tiny
MERLIN2021
  • EXPERT
Can you post the exact codes? Could be as simple as a pinced, or removed ground wire.
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Thursday, November 19th, 2009 AT 2:41 PM
Tiny
SILVESTRIK
  • MEMBER
The codes that appeared after the trans swap were: PO136, PO141
New O2 sensor installed and code is gone.
Repaired clutch speed sensor connector and code is gone.
Light remains on.
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Thursday, November 19th, 2009 AT 2:47 PM
Tiny
MERLIN2021
  • EXPERT
So the ecm has no stored codes, but the MIL is lit? And no codes or freeze frame data are stored? Try removing negative battery cable for 1/2 hour. If no good, I will need to find a wirind diagram for the DLC(data link connector) to see if it has a short to power in the light circuit.
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Thursday, November 19th, 2009 AT 2:55 PM
Tiny
SILVESTRIK
  • MEMBER
Yes, I had disconnected the battery for 2 hours, no dice. I also pulled out the ECU fuse for a hour. Also no change.
This has everyone I talked to stumped. I replaced the ECU and no change.
We're to the point of desperation. I'm on umemployment and can't afford someone to tear the car apart to find the source of the problem.
Although, If you can help me fix it, I'll gladly make a larger donation to you folks, plus recommend you to others.
Ken S
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Thursday, November 19th, 2009 AT 3:04 PM
Tiny
MERLIN2021
  • EXPERT
Only two things come to mind, Readiness monitor is not ready, car needs to be driven a certain way which I will post, and the DLC 3 connector needs to be checked, I will post this as well:
DLC3 INSPECTION 1. If scan tester displays UNABLE TO CONNECT TO VEHICLE when scan tester is connected, try scan tester on another vehicle. If scan tester operates on another vehicle, go to next step. If scan tester does not operate on another vehicle, problem is probably with scan tester. 2. Check DLC3 for loose or damaged terminals. Ensure DLC3 terminals are in correct position in connector. See appropriate wiring diagram in WIRING DIAGRAMS article. Repair as necessary. If connector and terminals are okay, go to next step. 3. Check voltage and resistance between ground and specified terminal on DLC3. See DLC3 VOLTAGE & RESISTANCE SPECIFICATIONS table. See Fig. 1 . If voltage and resistance readings are not as specified, check wiring circuit. See appropriate wiring diagram in WIRING DIAGRAMS article. NOTE: Terminal No. 2 on DLC3 provides the pulse generation during the information transmission from the Engine Control Module (ECM).


http://www.2carpros.com/forum/automotive_pictures/62217_dlc_2.jpg


http://www.2carpros.com/forum/automotive_pictures/62217_2_39.jpg



http://www.2carpros.com/forum/automotive_pictures/62217_Monitor_Readiness_1.jpg


I will email a PDF on monitor driving instructions.
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Thursday, November 19th, 2009 AT 3:59 PM
Tiny
SILVESTRIK
  • MEMBER
Hi Mike,

Thank you so much for all this material.
My next opportunity for troubleshooting will be Saturday.
I'll let you know my findings.

Ken S
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Thursday, November 19th, 2009 AT 5:34 PM
Tiny
MERLIN2021
  • EXPERT
I will look in again later today, time to hang Chistmas lights. OOPS! Not allowed to say "Christmas" any more, "Holiday lights"!
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Saturday, November 21st, 2009 AT 10:13 AM
Tiny
SILVESTRIK
  • MEMBER
Hi,
I did the DLC 3 tests - all ok.
Could not locate a ground connection at the back of the intake manifold. Perhaps you can direct me via the attached images.
Images 4 and 5 show the earlier problem with the trans speed sensor. Since the connector was rotted, I soldered the leads directly to the sensor. The resistance of this sensor is in spec with the magnetic testing. The error code for this was cleared.
Please note: I'm able to clear the check engine light with a scanner when the car is running. However, when I shut the ignition off then on again, the light returns.


http://www.2carpros.com/forum/automotive_pictures/437263_DSCN0489_1.jpg



http://www.2carpros.com/forum/automotive_pictures/437263_DSCN0490_1.jpg



http://www.2carpros.com/forum/automotive_pictures/437263_DSCN0491_1.jpg



http://www.2carpros.com/forum/automotive_pictures/437263_DSCN0492_1.jpg



http://www.2carpros.com/forum/automotive_pictures/437263_DSCN0493_1.jpg



http://www.2carpros.com/forum/automotive_pictures/437263_DSCN0497_1.jpg

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Saturday, November 21st, 2009 AT 4:56 PM
Tiny
MERLIN2021
  • EXPERT
In the top picture, under the hose that connects with clamps, that looks like several ground wires, check that, remove and clean them up. The other possibilty is the ignition switch might be the cause.
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Saturday, November 21st, 2009 AT 7:22 PM
Tiny
SILVESTRIK
  • MEMBER
Hi,
I pulled and cleaned those ground wires, but no change.
How do I check the ignition switch?
This all began with the tranny swap. What else could have been affected in the process?
All the connectors look good.
We only have 2 days left before the inspection sticker expires. :-(
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Monday, November 23rd, 2009 AT 7:47 AM
Tiny
MERLIN2021
  • EXPERT
I would inspect all wires that may have been pinched by the swap. And inspect the electrical connector at the tranny. Look for bent or pushed out pins in the connector.
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+1
Monday, November 23rd, 2009 AT 8:43 AM
Tiny
SILVESTRIK
  • MEMBER
New information Mike:
I was able to clear the ck engine light while the car is running. We had hoped to have the car re-inspected without turning the car off and on again, where the light would return again. However we discovered that the light came back on when the car downshifted. We repeated this twice more to confirm. As a result, the re-inspection was aborted. Does this help to narrow our search for the cause of the problem?
If so, where do we look now?
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Monday, November 23rd, 2009 AT 3:39 PM
Tiny
MERLIN2021
  • EXPERT
Yes like I said inspect the wires to bothe the shift solenoids and the VSS(vehicle speed sensor). These are electrical connectors on your transaxle. One may have been pinched. When the MIL returns, are there any stored codes? Read both the codes and freeze frame data. This tells you under what conditions the codes were set.
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Monday, November 23rd, 2009 AT 8:28 PM
Tiny
SILVESTRIK
  • MEMBER
Hi Mike,

No codes appear - ever.
However, all these findings seem to point to the tranny swap.
With that, tomorrow we're bringing the car back to the garage that originally did the work and have asked them to check all these connections.
Also, the rep from the state RMV suggested that even though we replaced the tranny from the same model car, there may be slight wiring differences at the connectors.
We'll see what tomorrow brings and I'll let you know after.
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Monday, November 23rd, 2009 AT 9:28 PM
Tiny
SILVESTRIK
  • MEMBER
Good news Mike! Problem solved!
The mechanic put the car on the lift and was checking all the trans connectors when he found a dirty one at the front below the driver's side. This was visible only when cocking the wheel. The light stayed off during a test drive, so we took the car straight to the inspection station and got the inspection sticker.
The tranny now shifts smoother too.

It's finally over, after spending several hundred dollars needlessly.

Thanks so much for your help and guidance Mike.
I've already given out your site to my friends if they ever need help with their cars.

I have an 04 Pontiac Grand Prix GTP that has issues with the traction control...but that's for another day my friend.

Happy Thanksgiving to you!

Ken and Jared Silvestri


http://www.2carpros.com/forum/automotive_pictures/437263_DSCN0509_2.jpg

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Tuesday, November 24th, 2009 AT 2:39 PM

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