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Test DA - Introduction

NOTE: Perform this test only when Codes 21, 24, 28, 51, 54, 58, 61, 64, or 68 are received in QUICK TEST. Ambient air temperature must be at least 50°F (10°C) to receive valid input from ACT and VAT sensors. Engine coolant temperature must be greater than 50°F to pass KOEO Self-Test and greater than 180°F to pass KOER Self-Test. Voltage values in this test are based on a 5-volt VREF signal. Values may vary up to 15% due to sensor and VREF variations. For test results to be valid, avoid performing test in unusually hot or cold conditions.
NOTE: This Pinpoint Test is intended to diagnose the following components and circuits:
Fig 1: Temperature Sensor Circuits
G90I10957
Fig 2: Temperature Sensors Resistance & Voltage Chart
G90J10958
ENGINE COOLANT/AIR CHARGE TEMP. SENSOR RESISTANCE & VOLTAGE

Temperature °F (°C) Voltage (volts) Resistance (K ohms)
248 (120) .27 1.18
230 (110) .35 1.55
212 (100) .46 2.07
194 (90) .60 2.80
176 (80) .78 3.84
158 (70) 1.02 5.37
140 (60) 1.33 7.70
122 (50) 1.70 10.97
104 (40) 2.13 16.15
86 (30) 2.60 24.27
68 (20) 3.07 37.30
50 (10) 3.51 58.75
VANE AIR TEMP. SENSOR RESISTANCE & VOLTAGE

Temperature °F (°C) Voltage (volts) Resistance (K ohms)
248 (120) 0.38 0.11
230 (110) 0.46 0.14
212 (100) 0.56 0.19
194 (90) 0.76 0.25
176 (80) 0.95 0.33
158 (70) 1.19 0.44
140 (60) 1.49 0.60
122 (50) 1.84 0.83
104 (40) 2.23 1.18
86 (30) 2.65 1.70
68 (20) 3.07 2.50
50 (10) 3.46 3.77
32 (0) N/A 5.80

To prevent the replacement of good components, ensure the following non-EEC areas or components are not at fault: