Diagnostic Trouble Code (DTC) Information

2004 Volvo V70 L5-2.5L Turbo VIN 59 B5254T2SECTION Diagnostic Trouble Code (DTC) Information





Diagnostic trouble code (DTC) information

Condition




Diagnostic trouble code (DTC) ECM-91A7 is stored if the engine control module (ECM) registers, when the engine is running, that the required throttle angle (desired value) does not correspond with the actual throttle angle (actual value) in the throttle unit

Substitute value
The engine control module (ECM) shuts down the supply to the throttle unit damper motor. The throttle will set itself to the return position

Possible source

Faulty signal:
- The throttle is sticking or is blocked (oil film, dust etc.)
- Contact resistance or oxidation in the terminals between the engine control module (ECM) and the throttle unit
- Open-circuit, short-circuit to ground or short-circuit to supply voltage in the wiring for the damper motor in the throttle unit
- Short-circuit to each other in the wiring for the damper motor in the throttle unit
- Defective throttle unit.

Fault symptom[s]
- Malfunction indicator lamp (MIL) lit
- Poor performance.

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.