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LOCATION:    7.1 Speed-sensitive Power Steering (SPS)   >   11 Electrical Test Program - Diagnostic Trouble Code (DTC) Memory


Electrical Test Program - Diagnostic Trouble Code (DTC) Memory

Test Preparation for DTC Readout
1. Connect impulse counter scan tool or Hand-Held Tester to data link connector (X11/4) as shown in section 0.

Note:
Connect yellow wire from impulse counter scan tool as follows:
SPS control module (N49/1) socket 12
Base module (N16/1) socket 8

2. Ignition: ON.

3. Read DTC memory of SPS control module (N49/1), and base module (N16/1).

Equipment
Hand-Held Tester (HHT) see applicable Service Information in groups 58
and 99

Model 140.0 (LH-SFI up 05/93), 140.1 (diesel)
Diagnostic trouble code (DTC)
Possible cause Test step/Remedy 1)
No fault recognized. In case of complaint: 23 (entire test)
Speed-sensitive power steering control module (N49/1) N49/1
Rear axle/left rear axle vehicle speed signal malfunction 23 7.0
Right rear axle vehicle speed signal malfunction 23 6.0
Comparison of left and right rear axle vehicle speed signals malfunctioning 23 7.0
Vehicle speed signal from axle missing 23 7.0
Vehicle speed signal from transmission missing 23 5.0
Short circuit between speed sensitive power steering P-valve (Y10) (+)
and UBATT		 23 4.0
Speed-sensitive power steering P-valve (Y10), short circuit 23 4.0
Speed-sensitive power steering P-valve (Y10), open circuit 23 4.0
Voltage supply to speed-sensitive power steering control module (N49/1) insufficient voltage 23 1.0
1) Observe Preparation for Test, see 22.

Model 140.0 (HFM-SFI and LH-SFI as of 06/93)
Diagnostic trouble code (DTC)
Possible cause Test step/Remedy 1)
No fault recognized. In case of complaint: 23 (entire test)
Speed-sensitive power steering control module (N49/1) N49/1
Comparison of axle vehicle speed signal status/left front axle vehicle speed signal malfunctioning 23 7.0
23 8.0
Axle vehicle speed signal status missing 23 8.0
Speed-sensitive power steering control module (N49/1) N49/1
Speed sensitive power steering P-valve (Y10); short circuit 23 4.0
Speed sensitive power steering P-valve (Y10); open circuit 23 4.0
Short circuit between speed sensitive power steering P-valve (Y10) (+)
and UBATT		 23 1.0
1) Observe Preparation for Test, see 22.



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