Tools - Fault Tracing Electronic Systems
SECTION2
GROUP
28
NO.
809
DATE
Sept. -95
Fault tracing electronic systems
800
REFERENCE:
SP 0314/2, VOLVO SPECIAL TOOLS - SYSTEM TESTER ST AND BREAK OUT BOX, REFERENCE GUIDE
This Service Bulletin replaces the earlier SB 28 809 of August 1994 which should be discarded.
Fault tracing electronic systems
This Service Bulletin contains information on using Volvo diagnostic tools for electronics. The introduction of Diagnose 2 on 1998 vehicles represents an important change in electrical diagnostics on the 850. The SRS, Combined Instrument, Power Seats*), Motronic 4.4 engine Management (including OBD II), Automatic Transmission, ABS/TRACS and Cruise Control systems all have diagnose 2 capability. All systems diagnosed using the Volvo Scan Tool (ST) are accessed at the passenger compartment DLC. The engine compartment DLC has been deleted for 1996.
The ST MUST BE connected to the Engine compartment DLC on all 1993-1995 850s. Although the 1994 turbo and 1995 automatic transmission versions contain a passenger compartment DLC, ST diagnostics are not accessible. The ST will not respond correctly when connected to the wrong DLC location.
The Volvo Test Box is an aid to carrying out measurements on management systems and wiring. It is used in combination with a multimeter, ohmmeter or voltmeter.
NOTE:
Many systems are reset when their power is turned off. Always read off diagnostic trouble codes (DTCs) before the test box adaptor is connected between the control module and cables.
NOTE:
These instruments are NOT a substitute for Service Manuals for diagnostic procedures, they should be used in accordance with the instructions contained in Service Manuals.
The ST is a microprocessor-based instrument for fault tracing electronic ignition and fuel injection systems. As the instrument can be connected while the car is being test driven, it is particularly suitable for tracing intermittent faults. It can also be used to monitor values such as the adaptive fuel trim functions.
A new adaptor and new wiring have been developed to connect the ST to the modified DLC on the 800 series from model year 1996.
*) Some early production 1996 model year 850s will not have Diagnose 2 capabilities on the power seat system.
800 Series