P0074 Valve electrical fault
Discussion
Hi all
2006 V8 Vantage owner. Parked the car up for a 2-3 weeks and when I came back to it I had a few faults on the dash all relating to brakes.
Brake failure stop safely
Emergency brake assist failure
Traction control temporary off
Using the Foxwell scanner there is only one fault logged in the brake module. I've already taken the car for a long run and cleared codes to make sure it's not a voltage issue but the code comes straight back after clearing.
It's P0074 valve electrical fault
Does anyone have any experience with this code?
2006 V8 Vantage owner. Parked the car up for a 2-3 weeks and when I came back to it I had a few faults on the dash all relating to brakes.
Brake failure stop safely
Emergency brake assist failure
Traction control temporary off
Using the Foxwell scanner there is only one fault logged in the brake module. I've already taken the car for a long run and cleared codes to make sure it's not a voltage issue but the code comes straight back after clearing.
It's P0074 valve electrical fault
Does anyone have any experience with this code?
gds54 said:
Hi all
2006 V8 Vantage owner. Parked the car up for a 2-3 weeks and when I came back to it I had a few faults on the dash all relating to brakes.
Brake failure stop safely
Emergency brake assist failure
Traction control temporary off
Using the Foxwell scanner there is only one fault logged in the brake module. I've already taken the car for a long run and cleared codes to make sure it's not a voltage issue but the code comes straight back after clearing.
It's P0074 valve electrical fault
Does anyone have any experience with this code?
My first thought if all these just appeared after 2-3 weeks standing is battery voltage. Did you have it on a battery conditioner while it was parked?2006 V8 Vantage owner. Parked the car up for a 2-3 weeks and when I came back to it I had a few faults on the dash all relating to brakes.
Brake failure stop safely
Emergency brake assist failure
Traction control temporary off
Using the Foxwell scanner there is only one fault logged in the brake module. I've already taken the car for a long run and cleared codes to make sure it's not a voltage issue but the code comes straight back after clearing.
It's P0074 valve electrical fault
Does anyone have any experience with this code?
LTP said:
My first thought if all these just appeared after 2-3 weeks standing is battery voltage. Did you have it on a battery conditioner while it was parked?
It was my first thought too. Unfortunately it wasn't possible to leave it plugged in so I trickle charged it all day before I left and when I got back. Battery appears ok, car starts ok etc. Have given it a long run to make sure it's fully charged and the code persists.Hi,
I'd like to weigh in on the P0074.
A P0074 is a power train code. With any P0xxx OBD code, it means the same thing on any OBDII car. It reports that the ambient air temperature sensor circuit is intermittent. The ECM relies on correct ambient air temps for a variety of reasons, some of which are:
fueling
Assisting (via fuel cutoff) in anti skid controls
assisting in ABS braking via engine control.
Modifying skid and braking controls when at the threshold of freezing temps
When the ambient temp sensor is intermittent and is not sending consistent signals to the ECM, the ECM will send dash messages along with the P0074 to alert the driver not to expect anti skid and ABS to work as expected because the ECM has faulty data being inputted. When the P0074 is "fixed" the other dash warnings usually extinguish as well (No repair interventions needed for these).
Back to the P0074 - the fault can be a few different things:
faulty ambient air temp sensor (most likely)
damaged wiring to/from the sensor (possible)
damaged harness connectors to/from the sensor (less likely)
If this were my problem, I'd probably first go to the sensor, maybe try another one, but only after I gave the wiring a good inspection. If wiring looks good, replace the sensor, erase the P0047 (delete code with a scan tool) then test drive, see if all messages are gone.
I'd like to weigh in on the P0074.
A P0074 is a power train code. With any P0xxx OBD code, it means the same thing on any OBDII car. It reports that the ambient air temperature sensor circuit is intermittent. The ECM relies on correct ambient air temps for a variety of reasons, some of which are:
fueling
Assisting (via fuel cutoff) in anti skid controls
assisting in ABS braking via engine control.
Modifying skid and braking controls when at the threshold of freezing temps
When the ambient temp sensor is intermittent and is not sending consistent signals to the ECM, the ECM will send dash messages along with the P0074 to alert the driver not to expect anti skid and ABS to work as expected because the ECM has faulty data being inputted. When the P0074 is "fixed" the other dash warnings usually extinguish as well (No repair interventions needed for these).
Back to the P0074 - the fault can be a few different things:
faulty ambient air temp sensor (most likely)
damaged wiring to/from the sensor (possible)
damaged harness connectors to/from the sensor (less likely)
If this were my problem, I'd probably first go to the sensor, maybe try another one, but only after I gave the wiring a good inspection. If wiring looks good, replace the sensor, erase the P0047 (delete code with a scan tool) then test drive, see if all messages are gone.
Thanks for the reply. Apparently Aston's body codes do not follow the OBD standard.
To conlude the thread, it ended up being the ABS module at fault, a valve inside it had failed. Main dealer diagnosed and replaced the module at significant expense, but at least she's fault free again!
To conlude the thread, it ended up being the ABS module at fault, a valve inside it had failed. Main dealer diagnosed and replaced the module at significant expense, but at least she's fault free again!
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