Why won't my highlander shift in to 4th gear?

Asked by Mar 28, 2015 at 08:13 AM about the 2007 Toyota Highlander Base AWD

Question type: Maintenance & Repair

The highlander won't shift to 4th gear at high speed. No lights show on dash but P0606
and P0138 codes show when car is scanned

5 Answers

34,955

PO138-- Faulty Rear Heated Oxygen Sensor Bank 1 - Rear Heated Oxygen Sensor Bank 1 harness is open or shorted - Rear Heated Oxygen Sensor Bank 1 circuit poor electrical connection - Intake air leaks - Exhaust gas leaks - Inappropriate fuel pressure - Faulty fuel injectors Replacing the Rear Heated Oxygen Sensor Bank 1 usually takes care of the problem. PO606- Faulty Engine Control Module (ECM) - Engine Control Module (ECM) Harness power supply circuit is open or shorted - Engine Control Module (ECM) Programming Check the ECM fuse, if fuse is OK try erasing the code first and if the code comes back you may have to reprogram or replaced the ECM.

1 out of 1 people think this is helpful.
34,955

Long story short, replace Rear O2 sensor on bank I and try to clear the PO606 code. If it won't clear, you will either have to reprogram the ECU or replace it. But check the ECU fuse first. The ECU issue may be your shifting issue also.

1 out of 1 people think this is helpful.
Best Answer

Thanks Reelin68. Do you think replacing O2 sensor combined with either clearing P0606 code or reprogramming ECU can eliminate shifting issue? I am really hoping I don't have to replace the unit. I heard it can cost a couple thousand dollars!! Can a used unit suffice if that is required?

34,955

Not sure if that will cure your shift issue. It may. If code persists, you will have to try reprogramming it or getting another. I would try Ebay or local salvage yard. Or you can remove your ECU and send it to these guys and they send you back a fresh rebuild for $189. SIA Electronics Toyota ECM ECU PCM Toyota Engine Computer Repair & Return SIA Electronics has many other repair services available. (800)737-0915 This listing is a REPAIR for your Toyota ECM/ECU/PCM. All Models and Years.

1 out of 1 people think this is helpful.

No, replacing O2 sensor will not help the shift issue. It will repair a fuel trim issue.In return give you a negligible gas milage and power gain should you decide to repair the transmission. There is a low probability that the shift solenoid will repair it. More than likely the $3500 boat anchor attached to your engine needs to be rebuilt, or replaced.

Your Answer

Add photo

Related Questions

Highlander

Looking for a Used Highlander in your area?

CarGurus has 22,076 nationwide Highlander listings starting at $2,000.

ZIP:

Search Toyota Highlander Questions

UK Questions

Are you a UK consumer? CarGurus now has a discussion forum in the UK.

Toyota Highlander Experts

#1 Wendy Tucker
Wendy Tucker
Reputation 3,670
#2 Tom Demyan
Tom Demyan
Reputation 3,560
#3 Shawntele Lewis
Shawntele Lewis
Reputation 2,350
View All

Related Models For Sale

Used Honda Pilot
527 Great Deals out of 19,336 listings starting at $950
Used Toyota 4Runner
341 Great Deals out of 20,329 listings starting at $1,250
Used Toyota RAV4
822 Great Deals out of 53,147 listings starting at $2,199
Used Acura MDX
332 Great Deals out of 15,701 listings starting at $2,194
Used Toyota Highlander Hybrid
28 Great Deals out of 1,129 listings starting at $4,431
Used Toyota Camry
1,199 Great Deals out of 93,146 listings starting at $700
Used Ford Explorer
1,207 Great Deals out of 71,146 listings starting at $1,000
Used Toyota Sienna
318 Great Deals out of 25,972 listings starting at $1,000
Used Nissan Pathfinder
504 Great Deals out of 24,526 listings starting at $1,795
Used Honda CR-V
907 Great Deals out of 66,880 listings starting at $1,995
Used Lexus RX 350
492 Great Deals out of 15,736 listings starting at $5,988
Used GMC Acadia
822 Great Deals out of 41,724 listings starting at $3,442
Used Toyota Tacoma
714 Great Deals out of 32,123 listings starting at $2,000
Used Toyota Sequoia
155 Great Deals out of 6,152 listings starting at $2,477
Used Jeep Grand Cherokee
1,000 Great Deals out of 65,966 listings starting at $1,500

Used Cars For Sale

2017 Toyota Highlander For Sale
7,117 listings starting at $18,577
2016 Toyota Highlander For Sale
20 Great Deals out of 3,173 listings starting at $24,995
2015 Toyota Highlander For Sale
95 Great Deals out of 1,742 listings starting at $19,995
2014 Toyota Highlander For Sale
64 Great Deals out of 1,072 listings starting at $18,998
2013 Toyota Highlander For Sale
155 Great Deals out of 2,612 listings starting at $14,790