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The 1-4-1 is the pedal sensor, the 1-4-2 is the brake light switch. Do you have both codes?
Mike
'95 850T
DTC 1-4-1: FAULTY PEDAL SENSOR, SHORT TO GROUND OR VOLTAGE
1) Connect test box to control module. See Fig. 3. Check
pedal sensor circuit by connecting jumper wires between test box
terminals No. 1, 2, 21, 34, and 36. Connect an ohmmeter between test
box terminals No. 16 and 41. Ohmmeter should indicate about 249 ohms.
2) Turn ignition on. Depress brake pedal as far as possible
and hold in place. Turn ignition off. Slowly release brake pedal while
at same time taking readings from ohmmeter. It should be possible to
observe 7 distinct resistance readings. See BRAKE PEDAL RESISTANCE
READINGS table.
BRAKE PEDAL RESISTANCE READINGS TABLE
Position OHMS
---------------------------------------------------------------
7 (Pedal Fully Depressed) ....................... Infinite
6 ................................................... 1032
5 .................................................... 817
4 (Pedal Midway) ..................................... 690
3 .................................................... 563
2 .................................................... 436
1 (Pedal Fully Released) ............................. 249
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3) If one resistance reading is incorrect, check wiring for
short circuits. If wiring is okay, replace pedal sensor. Compare color
of pedal sensor spacer sleeve with power brake booster color code. If
all resistance readings are correct, replace control module.
For the 1-4-2:
DTC 1-4-2: FAULTY BRAKE LIGHT SWITCH, OPEN OR SHORT CIRCUIT
1) Check if brakelight works. If brakelight does not work,
check bulb and wiring as necessary. If brakelight works, connect test
box to control unit. Connect voltmeter between test box
terminals No. 32 and 1 (Hot and Ground). Depress brake pedal. If voltmeter indicates battery voltage, erase DTC and test drive vehicle.
If DTC occurs again,
replace control module. If voltmeter does not indicate battery
voltage, go to next step and check if circuit is open or shorted.
2) Remove 2 wires (Red and Yellow wires) from brakelight
switch. Connect voltmeter between Red wire and ground. If battery
voltage is present, go to next step. If battery voltage is not
present, check wiring or fuse for an open circuit.
3) Connect a jumper wire between Red and Yellow wires. If
brakelight lights, ensure brakelight switch is adjusted correctly. If
switch is adjusted correctly, replace switch. If brakelight does not
light, ensure wiring to brakelight bulbs is okay.
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