VOLVO
ECM-903F - Throttle position (TP). Signal missing. Intermittent fault
System
Engine Control Module (ECM)
Volvo models this fault code applies to
This fault code has different meanings depending on model, model year or engine. Select the meaning that applies to your car.
Applies to the following models:
5 modelsC70 Cabriolet (1998–2005), C70 Coupé (1998–2002), S70 (1997–2000), V70 (1997–2000), V70 XC (1998–2000)
Show models by year and engine (10)
- Volvo C70 Cabriolet (1998–2005)1999, 2001–2002
- Volvo C70 Cabriolet (1998–2005)2000All engines except: B5244S
- Volvo C70 Coupé (1998–2002)1999All engines except: B5254S DENSO
- Volvo C70 Coupé (1998–2002)2000All engines except: B5244S
- Volvo C70 Coupé (1998–2002)2001–2002
- Volvo S70 (1997–2000)1999Engine B5204T3, B5204T4, B5234T3, B5234T7, B5254T only
- Volvo S70 (1997–2000)2000Engine B5204T3, B5204T4, B5234T3, B5234T7, B5244T only
- Volvo V70 (1997–2000)1999Engine B5204T3, B5204T4, B5234T3, B5234T7, B5234T8, B5254T only
- Volvo V70 (1997–2000)2000All engines except: B5244S, B5244S2, B5244SG, B5244SG2, D5252T MSA 15.8
- Volvo V70 XC (1998–2000)1999–2000
What does this fault code mean?
The engine control module (ECM) compares the desired throttle angle with the actual angle, which the throttle module (ETM) reports over CAN. The fault is intermittent: it has occurred on an earlier occasion but is not present right now. The code is set when the actual angle is missing while the desired angle is steady.
Possible causes
- The throttle module receives too low a supply, for example from loose connections or low system voltage
- Damaged CAN wires
- Interference on the CAN signal wires
- A damaged throttle module
What you can do
- 1If you have diagnostic equipment, read the code status; if it shows the fault is not present now, it has been intermittent
- 2Look for damaged CAN wires and connectors, and use a multimeter to check that the wires have no short to ground or voltage and no break that comes and goes
- 3Check the battery and its connections for contact resistance and oxidation, so that the throttle module receives a steady supply
- 4With the ignition on, gently move the harness and connectors to see whether the fault returns
- 5Clear the code and road test the car to see whether it comes back
- 6If the fault returns, have a workshop check the throttle module and the control modules in the CAN network
Symptoms you may notice4
- The accelerator pedal is ignored when braking
- Cruise control cannot be engaged
- Uneven idle
- Jerking during engine braking
What the fault can affect3
- The throttle closes when braking
- Engine speed is controlled by fuel cut-off, so idle may feel uneven
- Cruise control is off during the driving cycle in which the fault was detected
General guidance for car owners. Diagnosis on the car can point to a different cause.