Check engine light is on

Tiny
CRAIGP1148
  • MEMBER
  • 2003 TOYOTA COROLLA
  • 1.6L
  • 4 CYL
  • 2WD
  • AUTOMATIC
  • 200,000 MILES
I connected a obd2 to the car the wifi connects but it will not communicate with the car. It keeps telling me it cannot communicate with the car so I cannot get rid of the engine light. I have tried three different obd2 connectors same problem with all of them.
Saturday, November 10th, 2018 AT 4:45 AM

5 Replies

Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 54,144 POSTS
Hello,

There is a fuse ODB 7.5 amp that needs to be checked and if okay please check the ground at the ALDL connector. Here is a guide to help check for power and ground with the wiring diagrams for he connector so you can see how it works and the fuse location as well:

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

Check out the diagrams (below). Please let us know what you find. We are interested to see what it is.

Cheers, Ken
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Monday, November 12th, 2018 AT 11:10 AM
Tiny
CRAIGP1148
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  • 4 POSTS
I have checked the fuse that is okay, obd2 powers up and when it says linking to car it does not link. When I turn the key of it says turn key on to connect but it will not link to car.
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Thursday, November 15th, 2018 AT 6:47 PM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 54,144 POSTS
Does the car run? Here are other fuses you should check for power in the PCM diagrams. I would check the grounds as well. It sounds like the computer might be bad. Check the EFI relay as well.

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

and

https://www.2carpros.com/articles/how-to-check-wiring

Check out the diagrams (below). Please let us know what happens.

Cheers, Ken
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Friday, November 16th, 2018 AT 1:00 PM
Tiny
CRAIGP1148
  • MEMBER
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Hi Ken, the car starts fine if I have tried everything but still will not connect to the obd11. If I pull the battery lead of when I start the car the engine light goes off, but when I switch it off again and start switch the engine light stays on.
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Sunday, November 18th, 2018 AT 5:15 AM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 54,144 POSTS
If the wiring is okay and the scanner is working then the only thing it leaves is a bad PCM. I would try a used/rebuilt one and plug it to see what happens. Here is the location.

Please let us know what happens.
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Monday, November 19th, 2018 AT 11:41 AM

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