[vanolefan]

I have a 2008 Toyota Tundra 5.7L. I have a flashing 4LO, VSC indicators and non-flashing (solid) check engine light and traction control lights. The codes indicate P0125 and C1201. Is this an air injection pump issue or something else. I disconnected the battery and the lights went away, but they came back a few days later.

 

[Brian20]

Do your backup lights work?

 

[vanolefan]

yeah. I also checked all of the wheel speed sensor wires and they seem to be in good shape.

 

[ViktorG]

The codes indicate P0125 and C1201. Is this an air injection pump issue or something else.

P0125 is Insufficient Coolant Temperature For Closed Loop Fuel Control
C1201 is irrelevant, comes on whenever any other fail code is in the system.

Check your coolant level.
If it is fine, you may need a thermostat or coolant temperature sensor replacement.
Where does your engine coolant temp sit at on the gauge when fully warmed up?

 

[vanolefan]

Coolant was a bit low, temp is good. Upon further inspection I found some crystalized coolant on the top right corner of the radiator. It appears I have a small crack. I ordered a new radiator.

Would this cause the flashing 4LO, VSC indicators and traction control lights? Or do you think I may have another issue, like the AIP valve?

 

[mendonsy]

If the DTC scan does not indicate any other problems then don't waste your time and money trying to create them.

 

[vanolefan]

true. I will fix the radiator and hopefully the lights go away for good!

 

[Rlav]

Coolant was a bit low, temp is good. Upon further inspection I found some crystalized coolant on the top right corner of the radiator. It appears I have a small crack. I ordered a new radiator.

Would this cause the flashing 4LO, VSC indicators and traction control lights? Or do you think I may have another issue, like the AIP valve?

I've got the exact same symptoms you describe, even the crystalized coolant, same corner of the radiator. You remember what the fix was?

Sent from my LGMP450 using Tapatalk

 

[obtunded]

I had the same problem. Took it to Toyota. 3k to fix. Bought a bypass kit for 159. The lights still flash but the truck is not in sluggish mode

 

[obtunded]

Rutech is the brand I used. Took about an hour to put in.

 

[Rockporter]

Did you put the plates on?

How about the codes cleared and dash lights to stop flashing?

I am about to purchase an AIP bypass kit and could use advice on a which one is best. My truck is in limp mode with lights flashing and 2442 code. Had the pumps done at the dealer but only lasted 2 years. Last week the truck started with the flashing and limp mode but still drives fine except for low power.

Any advice would be much appreciated.

 

[mendonsy]

Paul Hewitt's kits are probably the best out there. https://hewitt-tech.com/

 

[Rockporter]

Thank you mendonsy. I may go with Hewitt. These air pumps in our trucks are total crap.

Also getting a 0051 code for an oxygen sensor that keeps coming up. Toyota dealer wants over $600 just for sensors, not including install. I may go to my local mechanic and ask him to hook it up to his code reader to look deeper into it before ordering anything. Toyota dealer is too expensive for me. Any advice?