VOLVO
TCM-0149 - Linear pressure solenoid SLB1. Signal too low
System
Transmission Control Module (TCM)
Volvo models this fault code applies to
Applies to the following models:
4 modelsS60 (2001–2009), V70 (2000–2008), V70 XC / XC70 (2001–2007), XC90 (2003–)
Show models by year and engine (9)
- Volvo S60 (2001–2009)2006–2007Engine B5254T4, D5244T4, D5244T5 only · Transmission TF-80SC, TF-80SC AWD only
- Volvo S60 (2001–2009)2008–2009Engine D5244T4, D5244T5 only · Transmission TF-80SC only
- Volvo V70 (2000–2008)2006–2007Engine B5254T4, D5244T4, D5244T5 only · Transmission TF-80SC, TF-80SC AWD only
- Volvo V70 (2000–2008)2008Engine D5244T5 only · Transmission TF-80SC only
- Volvo V70 XC / XC70 (2001–2007)2006–2007Engine D5244T4 only · Transmission TF-80SC AWD only
- Volvo XC90 (2003–)2006–2007Engine D5244T4 only · Transmission TF-80SC AWD only
- Volvo XC90 (2003–)2008–2010Engine D5244T4, D5244T5 only · Transmission TF-80SC AWD only
- Volvo XC90 (2003–)2011Engine D5244T18, D5244T4, D5244T5 only · Transmission TF-80SC, TF-80SC AWD only
- Volvo XC90 (2003–)2012All engines except: B5254T2, B6324S5 · All transmissions except: AW50/51 AWD
What does this fault code mean?
The fault concerns an open circuit in the circuit to linear pressure solenoid SLB1, even though it is named too low signal. The solenoid then cannot regulate the system pressure, which affects the lock-up function and gear changes.
Possible causes
- Contact resistance in the connectors
- Open circuit in the control signal or signal ground wire
- Linear pressure solenoid SLB1 does not function
- The TCM is not working
What you can do
- 1Clear the fault code and road test; if it returns, the break is probably still present
- 2If you have a diagnostic tool: read the SLB1 solenoid value in live data during a road test and see whether it changes
- 3Check that the wiring and connectors from the gearbox are secure and not corroded
- 4Use a multimeter to check that the wire to the SLB1 solenoid is intact along its whole length
- 5If the wire is intact, have a workshop decide whether the solenoid or the control module needs replacing
Symptoms you may notice4
- The general warning lamp is lit
- The malfunction indicator lamp is lit
- The lock-up function does not work
- Harsh gear changes
What the fault can affect1
- An auxiliary program in the control module is activated
General guidance for car owners. Diagnosis on the car can point to a different cause.