Now getting P1150 and P1151. I'm running out of ideas on how to solve these two. Could it be a bad O2 sensor or MAF?
02 GT throwing several codes, #8 fuse
- Thread starter Tripoli
- Start date
Did you try and find a single-line wiring diagram? That would help you trace the route of the circuit. I would remove everything from the circuit and take and resistance reading with your muitmeter. you should read no to very little resistance. If you read a fault start isolating parts of the circuit untill you find the part of circuit that is bad. Good luck!
Resurrecting this, 5 years later...
So, I thought I had fixed this issue by replacing part of a wire on my O2 extenders for my long tube headers. Got her on the dyno earlier this week for my D-1SC tune, and the tuner confirmed that the O2s were indeed working. I now have a closed loop tune again. On the way home from the tune, I threw good old P1451 again. Today, 2 days later, P0155 joined the party again as well. What's interesting this time around is the fuse hasn't blown.
I'm just about out of ideas. I went ahead and ordered new upstream oxygen sensors this morning, since I have yet to try replacing those. My best guess is that one of the heaters is bad.
So, I thought I had fixed this issue by replacing part of a wire on my O2 extenders for my long tube headers. Got her on the dyno earlier this week for my D-1SC tune, and the tuner confirmed that the O2s were indeed working. I now have a closed loop tune again. On the way home from the tune, I threw good old P1451 again. Today, 2 days later, P0155 joined the party again as well. What's interesting this time around is the fuse hasn't blown.
I'm just about out of ideas. I went ahead and ordered new upstream oxygen sensors this morning, since I have yet to try replacing those. My best guess is that one of the heaters is bad.
wmburns
SN Certified Technician
F2.8 engine sensor VPWR buss
Reading through the post, I am confused as to the state of the repairs and "hacking" done in the early attempts to locate the failure.
Note, there are a TON of sensors on the F2.8 buss. The RD/YE wire is "hot in start/run" and any ground fault will take out F2.8 as well as all of the connected powered sensors.
Componding this could be that your search has been for a ground fault. What if the RD/YE is also shorting out with the signal return? The PCM is expecting a very SPECIFIC voltage waveform from an O2 sensor. Stray voltage induced will certainly cause the PCM to go insane. I am going to go out on a limb here and say that there are two (or more) problems.
I am going to presume that the O2 extension wire was melted by the LT headers. I think you repaired the RD/YE circuit but have not correctly repaired the signal return. The code P0155 is very specific for the HO2S-21 O2 sensor (bank 2 (left) front).
The O2 sensors are vital for closed loop operation and a well running motor. If it were my car and I had ANY doubts about the O2 sensor, I would replace it. Once you are dealing with a known good sensor, then any additional O2 related DTC's can be addressed as a wiring fault.
Note, the O2 signal return is a tiny voltage. As such, any wiring extension should include shielding to prevent induced stray voltage. If the original wire was damaged, how did you repair the shield? If not, this may be the source of some of the problem.
Next. Suggest reviewing the splice made to restore power back the EVAP purge solenoids. Suspect that 5 years of water has taking it's toll.
>>from Ford Service CD
P1451 - EVAP Control System Canister Vent Solenoid Circuit Malfunction
Monitors the canister vent (CV) solenoid circuit for an electrical failure. The test fails when the signal moves outside the minimum or maximum allowable calibrated parameters for a specified canister vent duty cycle by PCM command. VPWR circuit open
CV solenoid circuit shorted to PWR GND or CHASSIS GND
Damaged CV solenoid
CV solenoid circuit open
CV solenoid circuit shorted to VPWR
Damaged PCM
Monitor EVAPCV PID and voltage between canister vent solenoid signal and PWR GND in output test mode with key ON engine OFF (or in key ON engine RUNNING mode)
EVAPCV PID at 0% and voltage less than 1.0 volt (or EVAPCV PID at 100% and voltage greater than 0.5 volt) indicates a hard fault
P0155 - HO2S Sensor Circuit Malfunction (HO2S-21) See DTC P0135
P0135 - HO2S Sensor Circuit Malfunction (HO2S-11)
During testing the HO2S Heaters are checked for opens/shorts and excessive current draw. The test fails when current draw exceeds a calibrated limit and/or an open or short is detected. Short to VPWR in harness or HO2S.
Water in harness connector.
Open VPWR circuit.
Open GND circuit.
Low battery voltage.
Corrosion or poor mating terminals and wiring
Damaged HO2S heater.
Damaged PCM.
Wiring.
Damaged HO2S heater.
Damaged PCM.
Reading through the post, I am confused as to the state of the repairs and "hacking" done in the early attempts to locate the failure.
Note, there are a TON of sensors on the F2.8 buss. The RD/YE wire is "hot in start/run" and any ground fault will take out F2.8 as well as all of the connected powered sensors.
Componding this could be that your search has been for a ground fault. What if the RD/YE is also shorting out with the signal return? The PCM is expecting a very SPECIFIC voltage waveform from an O2 sensor. Stray voltage induced will certainly cause the PCM to go insane. I am going to go out on a limb here and say that there are two (or more) problems.
I am going to presume that the O2 extension wire was melted by the LT headers. I think you repaired the RD/YE circuit but have not correctly repaired the signal return. The code P0155 is very specific for the HO2S-21 O2 sensor (bank 2 (left) front).
The O2 sensors are vital for closed loop operation and a well running motor. If it were my car and I had ANY doubts about the O2 sensor, I would replace it. Once you are dealing with a known good sensor, then any additional O2 related DTC's can be addressed as a wiring fault.
Note, the O2 signal return is a tiny voltage. As such, any wiring extension should include shielding to prevent induced stray voltage. If the original wire was damaged, how did you repair the shield? If not, this may be the source of some of the problem.
Next. Suggest reviewing the splice made to restore power back the EVAP purge solenoids. Suspect that 5 years of water has taking it's toll.
>>from Ford Service CD
P1451 - EVAP Control System Canister Vent Solenoid Circuit Malfunction
Monitors the canister vent (CV) solenoid circuit for an electrical failure. The test fails when the signal moves outside the minimum or maximum allowable calibrated parameters for a specified canister vent duty cycle by PCM command. VPWR circuit open
CV solenoid circuit shorted to PWR GND or CHASSIS GND
Damaged CV solenoid
CV solenoid circuit open
CV solenoid circuit shorted to VPWR
Damaged PCM
Monitor EVAPCV PID and voltage between canister vent solenoid signal and PWR GND in output test mode with key ON engine OFF (or in key ON engine RUNNING mode)
EVAPCV PID at 0% and voltage less than 1.0 volt (or EVAPCV PID at 100% and voltage greater than 0.5 volt) indicates a hard fault
P0155 - HO2S Sensor Circuit Malfunction (HO2S-21) See DTC P0135
P0135 - HO2S Sensor Circuit Malfunction (HO2S-11)
During testing the HO2S Heaters are checked for opens/shorts and excessive current draw. The test fails when current draw exceeds a calibrated limit and/or an open or short is detected. Short to VPWR in harness or HO2S.
Water in harness connector.
Open VPWR circuit.
Open GND circuit.
Low battery voltage.
Corrosion or poor mating terminals and wiring
Damaged HO2S heater.
Damaged PCM.
Wiring.
Damaged HO2S heater.
Damaged PCM.
As always, thank you for your help.
The new O2s are on the way. God willing they do the trick. As for the melted connector, I have replaced it with a new one. The suspect wire on the O2 extension has been cut out and replaced with a new one (the old one was just bare copper). Only about 1/4" of the bare wire is left, and it's thoroughly covered with electrical tape. I can't imagine it'd be shorting.
As for all the other hacking, well it's a bit of a mess. At this point, I couldn't tell you exactly what was cut, spliced, and bypassed, but I can tell you where I did it, and that it was all that RE/YE wire. One cut was made on the wire just above the PCM, leading into the fender well, and another was made right where the wires first enter the engine bay. At present, my bypass wires are still in place. The attempt was to bypass areas where wires could have rubbed through against metal, passing into and then out of the fender well (although there was no evidence this had occurred).
I believe I could remove all the bypassing, but I'm confused about one thing. There appear to be two RD/YE wires in the loom where I spliced into, after the wires have entered the engine bay. I'm concerned about splicing the correct pairs back together. I might be able to tell once I get in there, but I'm sitting at my desk job right now on this gorgeous day.
The new O2s are on the way. God willing they do the trick. As for the melted connector, I have replaced it with a new one. The suspect wire on the O2 extension has been cut out and replaced with a new one (the old one was just bare copper). Only about 1/4" of the bare wire is left, and it's thoroughly covered with electrical tape. I can't imagine it'd be shorting.
As for all the other hacking, well it's a bit of a mess. At this point, I couldn't tell you exactly what was cut, spliced, and bypassed, but I can tell you where I did it, and that it was all that RE/YE wire. One cut was made on the wire just above the PCM, leading into the fender well, and another was made right where the wires first enter the engine bay. At present, my bypass wires are still in place. The attempt was to bypass areas where wires could have rubbed through against metal, passing into and then out of the fender well (although there was no evidence this had occurred).
I believe I could remove all the bypassing, but I'm confused about one thing. There appear to be two RD/YE wires in the loom where I spliced into, after the wires have entered the engine bay. I'm concerned about splicing the correct pairs back together. I might be able to tell once I get in there, but I'm sitting at my desk job right now on this gorgeous day.
wmburns, as always, you seem to really know your stuff, and you were dead on with this one.
My new O2s came in last night, so I threw the car up on ramps and swapped them out. Without resetting the computer, I fired her up and drove her around for a few minutes, then checked the codes. P0155 was gone, but P1451 remained, so I reset the computer and tried again, and again P1451 popped up. I started poking around checking the wires, and wouldn't you know it, the harness for the EVAP canister had come unplugged. The clip seems to be worn out, so it had worked itself loose. Plugged that back in, reset the computer, and I am code-free!
Only took 2.5 years to figure this one out.
My new O2s came in last night, so I threw the car up on ramps and swapped them out. Without resetting the computer, I fired her up and drove her around for a few minutes, then checked the codes. P0155 was gone, but P1451 remained, so I reset the computer and tried again, and again P1451 popped up. I started poking around checking the wires, and wouldn't you know it, the harness for the EVAP canister had come unplugged. The clip seems to be worn out, so it had worked itself loose. Plugged that back in, reset the computer, and I am code-free!
Only took 2.5 years to figure this one out.
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