DTCM - Diagnostic Trouble Code Memory
Preliminary work: Diagnosis - Function Test. FT - Function Test
Preparation for DTC Readout:
1. Review DTC Memory and Actual Values.
2. Fuses OK.
3. Battery voltage 11 - 14 V
4. SRS MIL (A1e15) illuminates.
5. Connect Hand-Held Tester (HHT) as per connection diagram and readout DTC memory.
WARNING: Interrupt any electrical current from reaching the airbag unit.
- Do not connect battery trickle charger.
- Risk of Injury when performing diagnostic tests and repairs on components of the SRS system.
- Store both airbags and side airbags with opening surface pointing upward.
- Do not expose to temperatures above 100° C.
NOTE: As of 07/93, diagnostic trouble codes (DTC's) can only be read out and erased using the Hand-Held Tester (HHT).
Determine MB number of the SRS control module via HHT (See DTC Chart).
- The SRS control modules beginning with the number 000, the fault code 1 is valid.
- Those beginning with 001, the fault code 2 is valid.
NOTE: When installing additional accessories, observe harness clearances near SRS sensor lines.
Test equipment: Hand-Held Tester (HHT) (Available through the MBNA Standard Equipment Program.)
NOTE: A current fault is indicated by the DTC being highlighted in black. Additional detailed information is given with most DTC's, which will indicate possible faults conditions or portions thereof: (see image above).
Fault frequency and time span of the fault can be read by pressing the ! key.
Fault frequency: Faults are noted by frequency of occurrence, i.e.: 5 periodic faults, 5 occurances, eliminated 5 times.
Time span: The amount of time elapsed since last fault, or since fault eliminated itself.
Actual values: Four displays are possible (see image above)
Contrary to the DTC memory, actual values are updated continuously, even during diagnosis, so that, e.g.: by moving components, or connections and wiring harnesses, intermittent failures may be indicated, recognized.
Control Module Versions: Information regarding the AB control modules and Side airbag sensors can be readout:
- Model
- Manufacture location
- Manufacture date
- Daily manufacture number (as of 12/96 only)
DTC Chart (Part 1):
DTC Chart (Part 2):
DTC Chart (Part 3):
Preparation for DTC readout for Lower Control Field Control Module (N72) only
1. Connect Hand-Held Tester (HHT) as per connection diagram and readout DTC memory for lower control field control module (N72).
2. Listed below are only the DTC's pertaining to SRS
3. Fuses OK.
4. Battery voltage 11 - 14V
5. SRS MIL (A1e15) illuminates.
