slippery_beaver

Hello,

Some symptoms:

Trans sometimes seems to act weak/funny after a few hours of driving, especially in hot climate when climbing hill.

Shifts hard unless I wipe off the VSS on the rear case occasionally(approx every 200 miles)

Starts quickly when cold, but must hold key in start position for a few second when warmed up

Check Engine Light just came on so I read the codes

Read KOEO code 122 so I tested the (TPS) sensor: 5V supply/good ground/ but voltage did not go up from .05V when actuating throttle

Replaced TPS but code remains. I pulled test wire while codes were flashing, but it didn't go away. Code 122 remains as well as engine light. I have not disconnected the battery.

Any advise is welcome!

joshtowal

joshtowal

I would check for an open ground going to the computer (gray w/ white wire). You've got power, so that side of the circuit is ok. You aren't showing any codes for the EVP sensor, so we can assume that the problem is either the GY/W wire or the PCM itself.

joshtowal

If you wanted to check the other wire just to be safe, just check for continuity between the brown wire on the TPS and the brown wire on the EVP.

slippery_beaver

Thanks Josh, I will do that next...

slippery_beaver

Okay so I have checked continuity on the brown/white (.09), and the gray/white seems to have a good ground at the tps connector.

I cleared the codes and test drove about 5 miles and rechecked codes and got the same 122 for the koeo, and 212 (loss of idm input to pcm or spout circuit grounded) in the memory.

Engine light still on.

Does this mean it is likely in the computer, or does 212(memory) lead me elsewhere?

joshtowal

Did you check continuity for the gray/white wire? You'll have to unhook the wiring harness from the PCM to do that check.

slippery_beaver

I checked it by going from ground on the connector, to ground on the battery. I will disconnect the harness to check all the way to the pcm.

I also checked the resistance on the TPS and found that it does not increase at all when actuating the sensor. According to Haynes it should be 3 ohm closed, and about 350 when fully open. I am getting 1.5 ohm with no change. So I took the sensor back to the store, and tested another brand new one and got the same thing, no change in resistance when actuated. It does not seem right that both new sensors would be bad, but I gues it is possible. I put a new battery in my meter just to be sure, and got the same result. So after that I ordered the Ford/Motorcraft TPS on Amazon Prime...

slippery_beaver

I checked it by going from ground on the connector, to ground on the battery. I will disconnect the harness to check all the way to the pcm.

I also checked the resistance on the TPS and found that it does not increase at all when actuating the sensor. According to Haynes it should be 3 ohm closed, and about 350 when fully open. I am getting 1.5 ohm with no change. So I took the sensor back to the store, and tested another brand new one and got the same thing, no change in resistance when actuated. It does not seem right that both new sensors would be bad, but I gues it is possible. I put a new battery in my meter just to be sure, and got the same result. So after that I ordered the Ford/Motorcraft TPS on Amazon Prime...

joshtowal

While you're waiting for the new sensor, you can try this:

- Key "OFF".
- Disconnect TP sensor. Inspect for damaged or pushed out pins, corrosion, loose wires, etc. Service as necessary.
- Jumper VREF circuit to TP circuit at TP sensor vehicle harness connector.
- Run Key On Engine Off Self-Test.
NOTE: If no DTCs are generated, immediately remove jumper and go directly to DH13.
- Is DTC 123 or 121 present (ignore all other DTCs)?
Yes -- Replace TP sensor. Remove jumper. Rerun quick test.
No -- Remove jumper.Go to DH11.

VREF is the Gray/Red and TP circuit is the Gray/White.