Preliminary Procedure

Connect NGS tester to Data Link Connector (DLC). Using NGS tester, perform DATA LINK DIAGNOSTIC TEST. If NGS tester does not communicate with vehicle, see MODULE COMMUNICATIONS NETWORK - PICKUP article to diagnose network concern. If NGS tester displays NO RESP/NOT EQUIP for Generic Electronic Module (GEM), perform TEST U: NO COMMUNICATION WITH GEM under SYSTEM TESTS.
If NGS tester displays SYSTEM PASSED for GEM, retrieve and record continuous DTCs. Erase continuous DTCs. Perform GEM on-demand self-diagnostics using NGS tester. If any GEM DTCs are retrieved, perform appropriate test under SYSTEM TESTS. See GENERIC ELECTRONIC MODULE (GEM) DTC IDENTIFICATION table. If no DTCs are retrieved, perform appropriate test under SYSTEM TESTS. See SYMPTOM CHART table.

GENERIC ELECTRONIC MODULE (GEM) DTC IDENTIFICATION

DTC ⁽¹⁾

Description

Perform Test

B1322

Left Front Door Ajar Switch Circuit Short To Ground

⁽²⁾⁽³⁾W

B1323

Door Ajar Light Circuit Failure

B1325

Door Ajar Light Circuit Short To Voltage

B1330

Right Front Door Ajar Circuit Short To Ground

⁽³⁾W

B1426

Seat Belt Light Circuit Short To Voltage

B1428

Seat Belt Light Circuit Failure

B1462

Seat Belt Switch Circuit Failure

⁽³⁾X

C1751

Vehicle Speed Sensor Output Short To Voltage

C1752

Vehicle Speed Sensor Output Short To Ground

P0500

Vehicle Speed Signal Circuit Failure

⁽⁴⁾F

P1804

4WD High Indicator Circuit Failure

P1806

4WD High Indicator Circuit Short To Voltage

P1808

4WD Low Indicator Circuit Failure

P1810

4WD Low Indicator Circuit Short To Voltage

⁽¹⁾	Testing for DTCs not listed, see MODULE COMMUNICATIONS NETWORK - PICKUP article.

⁽²⁾	Test interior light wiring and repair as necessary. See appropriate wiring diagram in ILLUMINATION/INTERIOR LIGHTS article.

⁽³⁾	Perform wiggle test. Tap, move, and wiggle wiring harness and connectors while monitoring scan tool.

⁽⁴⁾	See appropriate WIPER/WASHER SYSTEMS article.

SYMPTOM CHART

Symptom	Go To Test
Fuel Gauge Inaccurate	A
Coolant Temperature Gauge Inaccurate	B
Oil Pressure Gauge Inaccurate	C
Speedometer Inaccurate	D
Speedometer/Odometer Inoperative (With 4-Wheel ABS)	E
Speedometer/Odometer Inoperative (With Rear ABS)	F
Tachometer Inoperative	G
Tachometer Inaccurate	H
Charge Indicator Always/Never On	J
Anti-Lock Brake Warning Light Inoperative	K
Fuel Reset Light Inoperative	L
High Beam Indicator Inoperative	M
Check Engine Light Inoperative	N
Turn Indicator Inoperative	P
Overdrive (O/D) Off Indicator Inoperative	Q
Cruise Control Indicator Never/Always On	R
Brake Warning Light Inoperative	S
Check Gauges Indicator Inoperative	T
No Communication With GEM	U
Air Bag Indicator Inoperative	V
Door Ajar Indicator Inoperative	W
Seat Belt Warning Indicator Inoperative	X
4WD High, 4WD Low Indicator Inoperative	Y