98 - Air Bag Light

[UMarquette]

Hello,

Just bought a '98 Continental with 100,000 miles on it from a big Ford-Lincoln-Mercury dealer in the area. I had no problems with it when I test drove it, and now 3 days later the air bag light is flashing for a few minutes after I start the car and then it stays on steadily. First, what might this be and how can I fix it, and second, is there any way the dealer could have turned this off while people were test driving it? The car came with no warranty, but aren't they still responsible for that if they didn't disclose it to me when I bought it? Thanks for your help.

Tim

[UMarquette]

I heard the pattern of how the light blinks may determine what the problem is, so I counted how it blinked.

The air bag light flashed in 10 sets of 3 blinks. It would blink 3 times in then go blank before beginning another set of 3. After 10 sets, it stayed on constantly.

I hope this might help solve the problem.

[Towncar]

Hmmm. What's that, a code 33 ??

Sorry for the messy format, this dosn't copy well from the book. I don't see an exact procedure for reading the LFC (lamp fault code) but I suspect it's saying 33. Here's the whole chart regardless:

Air Bag Diagnostic Monitor Diagnostic Trouble Code (DTC) Index Table


³ DTC ³ LFC ³ Description ³ Action To Take ³
³ B1342 ³ 24 ³ Internal microprocessor fault ³ GO to Pinpoint Test A. ³
³ ³ ³ (retrieved only during on-demand ³ ³
³ ³ ³ self test) ³ ³
³ B1867 ³ 12/52 ³ Lost battery feed or low battery ³ GO to DTC B1867. ³
³ ³ ³ feed voltage ³ ³
³ B1869 ³ Ä ³ No air bag indicator - Inoperative ³ GO to Pinpoint Test C. ³
³ ³ ³ indicator circuit ³ ³
³ B1913 ³ 13/53 ³ Air bag driver/passenger circuit ³ GO to DTC B1913. ³
³ ³ ³ short to ground ³ ³
³ B1914 ³ 14/54 ³ Primary crash sensor circuit shorted ³ GO to DTC B1914. ³
³ ³ ³ to ground ³ ³
³ B1921 ³ 21 ³ Air bag diagnostic monitor ground ³ GO to DTC B1921. ³
³ ³ ³ circuit open or not mounted to ³ ³
³ ³ ³ vehicle properly ³ ³
³ B1922 ³ 22 ³ Safing sensor output circuit shorted ³ GO to DTC B1922. ³
³ ³ ³ to battery voltage ³ ³
³ B1923 ³ 23 ³ Memory clear circuit improperly ³ GO to DTC B1923. ³
³ ³ ³ grounded ³ ³
³ B1924 ³ 24 ³ System disarm failure or internal ³ GO to Pinpoint Test A. ³
³ ³ ³ diagnostic monitor fault ³ ³
³ B1932 ³ 32 ³ Driver side air bag high resistance ³ GO to DTC B1932. ³
³ ³ ³ or open ³ ³
³ B1933 ³ 33 ³ Passenger side air bag circuit high ³ GO to DTC B1933. ³
³ ³ ³ resistance or open ³ ³
³ B1934 ³ 34 ³ Driver side air bag circuit low ³ GO to DTC B1934. ³
³ ³ ³ resistance or shorted ³ ³
³ B1935 ³ 35 ³ Passenger side air bag circuit low ³ GO to DTC B1935. ³
³ ³ ³ resistance or shorted ³ ³
³ B1941 ³ 41 ³ RH primary crash sensor feed/return ³ GO to DTC B1941. ³
³ ³ ³ circuit open ³ ³
³ B1942 ³ 42 ³ LH primary crash sensor feed/return ³ GO to DTC B1942. ³
³ ³ ³ circuit open ³ ³
³ B1944 ³ 44 ³ RH primary crash sensor not mounted ³ GO to DTC B1944. ³
³ ³ ³ to vehicle properly or ground ³ ³
³ ³ ³ circuit open ³ ³
³ B1945 ³ 45 ³ LH primary crash sensor not mounted ³ GO to DTC B1945. ³
³ ³ ³ to vehicle properly or ground ³ ³
³ ³ ³ circuit open ³
DTC - Diagnostic trouble code, retrieved using New Generation Star (NGS) Tester 007-00500 or equivalent.
LFC - Lamp fault code, flashed on air bag indicator.



DTC B1933: PASSENGER SIDE AIR BAG CIRCUIT HIGH RESISTANCE OR OPEN--LAMP FAULT CODE 33

Normal Operation

Note: The air bag connector and the air bag diagnostic monitor harness connector have metal spring clips that act as shorting bars. These shorting bars are built into the plastic hardshell connectors. The shorting bars are designed to short Circuit 607 (LB/O) and 616 (PK/BK) together when the connectors are not mated. DO NOT attempt to remove the air bag shorting bar and measure the resistance of the air bag.

The shorting bar(s) in the air bag diagnostic monitor harness connector may be removed by removing the black spacer (locking wedge) from the connector. Use extreme caution when reinstalling the spacers to make sure they are installed correctly.

While the ignition switch is in the RUN position, the air bag diagnostic monitor runs periodic checks on the resistance of the driver and passenger air bag circuits.

l Normal resistance from Pin C1-5, Circuit 607 (LB/O)(passenger air bag feed) to Pin C1-4, Circuit 616 (PK/BK)(passenger air bag return) is between 0.9 ohm and 1.2 ohms. This resistance consists of the passenger air bag module resistance (approximately 1.0 ohm) plus a small amount of resistance due to the wire itself, crimps, etc.

l If the resistance across Pin C1-5, Circuit 607 (LB/O) and C1-4, Circuit 616 (PK/BK) exceeds 3 ohms, the air bag diagnostic monitor will store in memory DTC B1933 and flash lamp fault code 33 on the air bag indicator.

l If the high resistance is later serviced or otherwise falls into the normal range, DTC B1933 will be stored in memory.

Possible Causes

Excessive resistance across Pins C1-5, Circuit 607 (LB/O) and C1-4, Circuit 616 (PK/BK) can be caused by:

l an open circuit or high resistance in the wiring harness in either Pin C1-5, Circuit 607 (LB/O) or Pin C1-4, Circuit 616 (PK/BK) .

l an open circuit or high resistance in the passenger side air bag module. Do not attempt a direct resistance measurement of the air bag. Follow the diagnostic procedure to determine if the air bag resistance is higher than normal.


Electrical Schematic--Diagnostic Trouble Code B1933--Lamp Fault Code 33



² B1933-1: CHECK FOR HARD OR INTERMITTENT DTC
² B1933-2: MEASURE RESISTANCE
² B1933-3: CHECK AIR BAG DIAGNOSTIC MONITOR
² B1933-4: CHECK CIRCUIT 607 (LB/O) FOR OPEN
² B1933-5: CHECK FOR SERVICED DTC
² B1933-6: CHECK AIR BAG CONNECTIONS
² B1933-7: CHECK CIRCUITS 607 (LB/O) AND 616 (PK/BK)
² B1933-8: CHECK FOR OTHER DTCS

[UMarquette]

Thanks for the help, Steven.

I think I am going to let the dealer handle this one, although they are not covering it. I am going to see if the previous owner had this problem. That way, the dealer will have to cover it by law.

-Tim