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Home >> Suzuki >> 2011 >> SX4 Base, Standard >> Repair and Diagnosis >> Steering >> Power Steering >> Power Assisted Steering System (Electric) >> Diagnostic Information and Procedures >> DTC C1122: Engine Speed Signal >> DTC Troubleshooting
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DTC Troubleshooting

C1122: TROUBLESHOOTING FLOW CHART

Step Action YES NO
Was "EPS System Check" performed?  Go to Step 2. Go to EPS SYSTEM CHECK: ELECTRIC TYPE .
DTC check 
  1. Check ECM for DTC referring to DTC CHECK .

Is there any DTC(s) detected? 
Go to applicable DTC troubleshooting. Go to Step 3.
Engine speed signal circuit check 
  1. With ignition switch turned OFF, disconnect P/S control module connector.
  2. Check P/S control module connector for proper connection.
  3. If OK, turn ON ignition switch, measure voltage between "E11-12" wire terminal of P/S control module connector and vehicle body ground.

Is voltage 10 - 14 V? 
Go to Step 4. Go to Step 5.
ECM voltage check 
  1. With ignition switch turned OFF, connect P/S control module and ECM connectors.
  2. Check engine speed signal output referring to INSPECTION OF ECM AND ITS CIRCUITS .

Is it in good condition? 
Substitute a known-good P/S control module and recheck. Substitute a known good ECM and recheck.
Engine speed signal circuit check 
  1. Disconnect ECM connector.
  2. Check that engine speed signal circuit is as follows.
    • Insulation resistance of wire harness is infinity between "Engine speed signal circuit" terminal and other terminal at P/S control module connector.
    • Wiring harness resistance of "Engine speed signal circuit" is less than 1Ω.
    • Insulation resistance between "Engine speed signal circuit" and vehicle body ground is infinity
    • Circuit voltage between "Engine speed signal circuit" and ground circuit is 0 - 1 V with ignition switch turned ON.

Is it in good condition? 
Substitute a known good ECM and recheck. Repair or replace defective circuit.