Fault Code 127

Conditions For Fault Code - If resistance is too high or if voltage is too low for more than 40 seconds, DTC 127 will be stored.

Fault Symptom - SRS warning light is on, indicating a fault code is stored. Warning light does not come on when ignition is turned on.

Fault Source - There is a short to ground in cable or connectors between combination instrument and sensor module. See Fig 1.

Fig 1: Identifying Connection Terminals For Sensor Module

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Corrective Action

Fig 2: Locating Connector 24/1 & Connector "E"

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Fig 3: Identifying Connector 24/1

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Fig 4: Identifying Connector "E"

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1. Turn ignition on. If SRS warning light is on, go to step 2). If SRS warning light is off, Check SRS warning light bulb. If bulb is bad, replace bulb, clear codes and retest. If code 127 resets and SRS warning light is off, go to step 6). If bulb is okay, go to step 4).
2. If warning light is on, there is probably an open circuit in wiring harness between SRS sensor module and instrument cluster 5/1 connector "B" terminal No. 3. Turn ignition off. Disconnect negative battery wiring harness. Remove left soundproofing panel and knee bolster. Remove connector "E" from connector 24/1. See Fig 2.Check terminals in both connectors. If connectors are okay, go to next step. If connector "E"is defective replace wiring harness between connector and instrument cluster connector. If connector 24/1 is defective, replace SRS wiring harness.
3. Turn ignition on. Connect negative battery wiring harness. Connect voltmeter between ground and terminal No. 11 in "E" connector. If voltage is about 8 volts, go to step 4). If voltage is not about 8 volts, replace wiring harness between connector "E" and instrument cluster 5/1 connector "B".
4. Turn ignition off. Disconnect negative battery wiring harness. Locate and remove SRS sensor module. Sensor module is located under center console. Check wiring harness connector and terminals. If connector is okay, go to next step. If sensor module male connector is defective, replace sensor module. See SENSOR MODULE  under REMOVAL & INSTALLATION. Ensure proper system operation. Perform SYSTEM OPERATION CHECK . If female connector is defective, replace SRS wiring harness.
5. Check for resistance between sensor module connector terminal 7 and connector pin terminal No. 11 of connector "E". If resistance is zero ohms, replace sensor module. See SENSOR MODULE  under REMOVAL & INSTALLATION. Ensure proper system operation. Perform SYSTEM OPERATION CHECK . If resistance is infinity, replace SRS wiring harness.
6. Turn ignition off. Disconnect negative battery cable. Remove left soundproofing panel and knee bolster. Remove connector "E" from connector 24/1. See Fig 2. Check resistance between ground and terminal No. 11 in connector "E". If resistance is about 1000 ohms, go to next step. If resistance is not about 1000 ohms, replace wiring harness between connector 24/1 connector "E" terminal No. 11 and instrument cluster 5/1 connector "B" terminal 3.
7. Locate and remove SRS sensor module Sensor module is located under center console. Check resistance between ground and connector 24/1 where terminal No. 11 of connector "E" was connected. and connecting pin terminal 11 where disconnected connector was connected. See Fig 2.If resistance is infinity, replace sensor module. See SENSOR MODULE  under REMOVAL & INSTALLATION. Ensure proper system operation. Perform SYSTEM OPERATION CHECK . If resistance is not infinity, replace SRS wiring harness. Clear fault codes. Perform SYSTEM OPERATION CHECK  to verify repair. Recheck for fault codes.