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Q: Repair - engine harness on 2008 Toyota Yaris

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I bought this car used in Nov 2009 and today I found out I need a new engine harness. Is this common?
My check engine light was on so I took it to the dealer. They did a diagnostic and came back with cause: P0171 P0101, needs engine harness.
Unfortunately on the Yaris it is a common problem. Toyota has a warranty for 36 months / 36,000 miles for this problem, but if the car out of the warranty you need to pay for the repair.
The good thing is that the harness can be replaced in less than 2 hours.
Here is a TSB which tells a bit more:

Electrical - MIL ON/Multiple DTC's Set


November 5, 2008

M.I.L. "ON" DTC P010#, P0121, P0125, P0172, P035#, P2237, or P2238
Service Category
Engine/Hybrid System

Engine Control




Some 2007 - 2008 model year Yaris vehicles may exhibit a M.I.L. "ON" DTC condition with one of the following Diagnostic Trouble Codes (DTCs):
- P0101 - Mass Air Flow Circuit Range / Performance Problem

- P0102 - Mass Air Flow Circuit Low Input

- P0103 - Mass Air Flow Circuit High Input

- P0121 - Throttle / Pedal Position Sensor/Switch "A" Circuit Range/Performance Problem

- P0125 - Insufficient Coolant Temperature for Closed Loop Fuel Control

- P0172 - System Too Rich

- P035# - Ignition Coil "#" Primary / Secondary Circuit

- P2237 - Oxygen (A/F) Sensor Pumping Current Circuit / Open

- P2238 - Oxygen (A/F) Sensor Pumping Current Circuit Low

An improved engine wire harness has been developed to address this condition. Use the following repair procedure to diagnose and repair customer complaint vehicles.

Roy, on alldata you can subscribe to receive new TSBs. They will e-mail them to you.
There are so many from different manufacturers, its impossible to keep all in mind, I usually read them and later it could give a clue.

The cause stated: P0171 AND P0101, needs engine harness. I don't see P0171 on your list.
Since P0101 indicates a MAF sensor circuit problem the P0171 could relate to this even if it's not in the list.

I just left ma yaris today , code PO121 , 2months after warranty (34000km).They told me after diagnostics that I need a new harness (700 plus 350 labour) .Told them that i consider it ridiculous after such mileage,complaint went to Toyota,will see what happens tomorrow .
I bought an extended warranty after what happened to my previous Toyota. I think this might be my last Toyota. I'm looking into Hyundai's now.
$350 for labor?? It takes 1.8 hours to do. Do they have a $194 /hour labor rate?? This seems to be very high. Unfortunately the harness' retail price is around US$ 730.00.

@ Zee, the dealership told me it will take an entire day to do and to leave my car for the day.
Well, in the recall info above Toyota included the time allowance -among the part numbers and VIN# info - and it's 1.8 hours. Unfortunately it's in a graphic (picture?) format and I can't post it here, but if you post an e-mail I can send you the entire thing.

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