How do relays function in electrical systems, and what steps should be taken to test and replace a defective relay on Chevrolet Express?

Quite a number of electrical accessories in the vehicle use relays to pass current to the component, and if the relay is faulty, then the specified component will not function as expected. That fuse is more often found in the engine compartment fuse and relay box, while some are found in the several wiring harnesses underneath the instrument panel. The suspected faulty relay can be readily withdrawn and checked using a certain procedure or may be referred to a dealer service department or a competent repair shop and since the relays come as assemblies or assemblies of required relays that have become faulty, they must be replaced as a whole. Many of the relays utilized in these automobiles are termed as "ISO" relays and bear numerical suffixes referring to their typical circuit connections/uses; the ISO relays essentially have two classic types of terminal arrangements. In order to find out which wires are connected in which manner, the wiring diagram for the circuit in question must be consulted, and in the absence of this information the following facts may be helpful. The two terminals on the right are for the relay control circuit and connected to the relay coil while the other two are of the power circuit. In the energised state of the coil, the larger contacts of the power circuit are closed to allow energy to flow to the circuit loads. The control circuit is usually terminals 85 and 86; if the diode is present the 86 must go to battery positive and 85 to ground if the resistor is present either end of terminal 85 or 86 can be connected. Terminal 30 is used to link the unit to the battery voltage to the circuit loads while terminal 87 connects to the ground side of circuits. Continuity checks can be done on relay control coil using an ohmmeter by placing leads on the meter in correct polarity then switch the sides of lead to check for continuity in the other direction. If a resistor is present, the resistance should be equal whether in forward or reverse polarity, if a diode is present then resistance should be higher in forward polarity. Thus if there is an infinite resistance in normal as well as in the auxiliary circuit, it call for replacement of the relay. Once the relay is removed continuity should be tested between the power circuit terminals, there should be no continuity from terminal 30 to 87 when the circuit is de-energized. If a fused jumper wire is connected to terminal 86 and the positive battery terminal and another end of the relay to pin 85 to ground the relay should click. When the jumper wires are connected, there should be continuity between terminal number 30 and 87. Where any of the above tests fail, the relay should be replaced.

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25 Relays found

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Chevrolet Express RELAY ASM,ACSRY TIME DELAY CUTOFF *GRAY
Part Number: 13500114
$10.11 MSRP: $20.88
You Save: $10.77 (52%)
Ships in 1-2 Business Days
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Product Specifications
- Replaces: 12088567, 12135170, 19116057, 92199312, 12193606, 12135034, 19115080, 15328866, 15393412
- Warranty: This genuine part is guaranteed by GM's factory warranty.
Fits the following Vehicles:
- 2008-2020 Chevrolet Express | 1 TON CARGO EXPRESS, 1 TON CARGO SAVANA, 1 TON COMMERCIAL/RV CUTAWAY, 1 TON PASSENGER, 1/2 TON CARGO EXPRESS, 1/2 TON CARGO SAVANA, 1/2 TON PASSENGER EXPRESS, 1/2 TON PASSENGER SAVANA, 3/4 TON CARGO EXPRESS, 3/4 TON CARGO SAVANA, 3/4 TON PASSENGER EXPRESS, 3/4 TON PASSENGER SAVANA | 4 Cyl 2.8L Diesel, 6 Cyl 4.3L, 8 Cyl 4.8L, 8 Cyl 4.8L Flex, 8 Cyl 5.3L, 8 Cyl 6.0L, 8 Cyl 6.0L Flex, 8 Cyl 6.6L Diesel
- 1996-2002 Chevrolet Express | 1 TON CARGO EXPRESS, 1 TON COMMERCIAL/RECREATIONAL VEHICLE EXPRESS, 1 TON PASSENGER, 1/2 TON CARGO EXPRESS, 1/2 TON PASSENGER EXPRESS, 3/4 TON CARGO EXPRESS, 3/4 TON PASSENGER EXPRESS | 6 Cyl 4.3L, 8 Cyl 5.0L, 8 Cyl 5.7L, 8 Cyl 6.5L Diesel, 8 Cyl 7.4L, 8 Cyl 8.1L
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Chevrolet Express Relay Asm,Multiuse *Gray
Part Number: 13503102
$7.77 MSRP: $16.90
You Save: $9.13 (55%)
Ships in 1-2 Business Days
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Product Specifications
- Replaces: 12193604, 15328864, 12088592, 12177236, 12088576, 12193614, 12135175
- Warranty: This genuine part is guaranteed by GM's factory warranty.
Fits the following Vehicles:
- 2000-2002 Chevrolet Express | 1 TON CARGO EXPRESS, 1 TON COMMERCIAL/RECREATIONAL VEHICLE EXPRESS, 1 TON PASSENGER, 1/2 TON CARGO EXPRESS, 1/2 TON PASSENGER EXPRESS, 3/4 TON CARGO EXPRESS, 3/4 TON PASSENGER EXPRESS | 6 Cyl 4.3L, 8 Cyl 5.0L, 8 Cyl 5.7L, 8 Cyl 6.5L Diesel, 8 Cyl 7.4L
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Chevrolet Express RELAY ASM,FAN CONT
Part Number: 13503103
$5.19 MSRP: $11.29
You Save: $6.10 (55%)
Ships in 1-2 Business Days
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Product Specifications
- Other Name: Fan Relay, Fuel Pump Relay, Relay
- Replaces: 19115298, 12193612, 12135198, 12193602, 12077865, 12177234, 15328865, 21997408, 19116363
- Warranty: This genuine part is guaranteed by GM's factory warranty.
Fits the following Vehicles:
- 1996-2007 Chevrolet Express | 1 TON CARGO EXPRESS, 1 TON COMMERCIAL/RECREATIONAL VEHICLE EXPRESS, 1 TON COMMERCIAL/RV CUTAWAY, 1 TON PASSENGER, 1/2 TON CARGO EXPRESS, 1/2 TON PASSENGER EXPRESS, 3/4 TON CARGO EXPRESS, 3/4 TON PASSENGER EXPRESS | 6 Cyl 4.3L, 8 Cyl 4.8L, 8 Cyl 5.0L, 8 Cyl 5.3L, 8 Cyl 5.3L Flex, 8 Cyl 5.7L, 8 Cyl 6.0L, 8 Cyl 6.5L Diesel, 8 Cyl 6.6L Diesel, 8 Cyl 7.4L, 8 Cyl 8.1L
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Chevrolet Express Relay Asm,Multiuse
Part Number: 19118886
$53.35 MSRP: $115.98
You Save: $62.63 (54%)
Ships in 1-2 Business Days
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Product Specifications
- Other Name: RELAY, Fuel Pump
- Replaces: 12177235, 12135086, 12135005, 12193613, 12177233, 84095360, 12193601, 12193603, 12193611, 12135085, 12077867, 12077864, 12088577, 19131161
- Warranty: This genuine part is guaranteed by GM's factory warranty.
Fits the following Vehicles:
- 1997-2010 Chevrolet Express | 1 TON CARGO EXPRESS, 1 TON CARGO SAVANA, 1 TON COMMERCIAL/RECREATIONAL VEHICLE EXPRESS, 1 TON PASSENGER, 1/2 TON CARGO EXPRESS, 1/2 TON CARGO SAVANA, 1/2 TON PASSENGER EXPRESS, 1/2 TON PASSENGER SAVANA, 3/4 TON CARGO EXPRESS, 3/4 TON CARGO SAVANA, 3/4 TON PASSENGER EXPRESS, 3/4 TON PASSENGER SAVANA | 6 Cyl 4.3L, 8 Cyl 4.8L, 8 Cyl 4.8L Flex, 8 Cyl 5.0L, 8 Cyl 5.3L, 8 Cyl 5.3L Flex, 8 Cyl 5.7L, 8 Cyl 6.0L, 8 Cyl 6.0L Flex, 8 Cyl 6.5L Diesel, 8 Cyl 6.6L Diesel, 8 Cyl 7.4L, 8 Cyl 8.1L
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Chevrolet Express Flasher Assembly, Hazard Lamp & Turn Signal Lamp
Part Number: 25746427
$63.12 MSRP: $123.04
You Save: $59.92 (49%)
Ships in 1 Business Day
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Product Specifications
- Other Name: FLASHER, Chassis/Body Marker/Hazard; Flasher
- Warranty: This genuine part is guaranteed by GM's factory warranty.
Fits the following Vehicles:
- 2003-2007 Chevrolet Express | 1 TON CARGO EXPRESS, 1 TON COMMERCIAL/RV CUTAWAY, 1 TON PASSENGER, 1/2 TON CARGO EXPRESS, 1/2 TON PASSENGER EXPRESS, 3/4 TON CARGO EXPRESS, 3/4 TON PASSENGER EXPRESS | 6 Cyl 4.3L, 8 Cyl 4.8L, 8 Cyl 5.3L, 8 Cyl 5.3L Flex, 8 Cyl 6.0L, 8 Cyl 6.6L Diesel
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Chevrolet Express Relay
Part Number: 13500113
$8.14 MSRP: $15.36
You Save: $7.22 (48%)
Ships in 1-2 Business Days
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Product Specifications
- Other Name: RELAY, A/C Electrical; Fan Relay, Fuel Pump Relay, Horn Relay
- Replaces: 19116059, 88988889, 19116962
- Warranty: This genuine part is guaranteed by GM's factory warranty.
Fits the following Vehicles:
- 2009 Chevrolet Express | 1 TON CARGO EXPRESS, 1 TON COMMERCIAL/RV CUTAWAY, 1 TON PASSENGER, 1/2 TON CARGO EXPRESS, 1/2 TON PASSENGER EXPRESS, 3/4 TON CARGO EXPRESS, 3/4 TON PASSENGER EXPRESS | 6 Cyl 4.3L, 8 Cyl 4.8L, 8 Cyl 5.3L, 8 Cyl 6.0L, 8 Cyl 6.6L Diesel
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Chevrolet Express Relay Assembly, Auxiliary Storage Battery.
Part Number: 12135194
$70.13 MSRP: $152.45
You Save: $82.32 (54%)
Ships in 1 Business Day
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Product Specifications
- Other Name: RELAY, Voltage and Glow Plug; Relay
- Replaces: 92257335
- Warranty: This genuine part is guaranteed by GM's factory warranty.
Fits the following Vehicles:
- 2017-2024 Chevrolet Express | 1 TON CARGO EXPRESS, 1 TON COMMERCIAL/RV CUTAWAY, 1 TON PASSENGER, 3/4 TON CARGO EXPRESS, 3/4 TON PASSENGER EXPRESS, Van 3/4 Ton Cargo Express | 4 Cyl 2.8L Diesel, 6 Cyl 4.3L, 8 Cyl 4.8L Flex, 8 Cyl 6.0L, 8 Cyl 6.0L Flex, 8 Cyl 6.6L
- 2003-2007 Chevrolet Express | 1 TON CARGO EXPRESS, 1 TON COMMERCIAL/RV CUTAWAY, 1 TON PASSENGER, 1/2 TON CARGO EXPRESS, 1/2 TON PASSENGER EXPRESS, 3/4 TON CARGO EXPRESS, 3/4 TON PASSENGER EXPRESS | 6 Cyl 4.3L, 8 Cyl 4.8L, 8 Cyl 5.3L, 8 Cyl 6.0L, 8 Cyl 6.6L Diesel
- 1998-1999 Chevrolet Express | 1 TON CARGO EXPRESS, 1/2 TON CARGO EXPRESS, 3/4 TON CARGO EXPRESS | 8 Cyl 6.5L Diesel, 8 Cyl 7.4L
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Chevrolet Express Relay,Headlamp
Part Number: 15016745
$37.12 MSRP: $72.36
You Save: $35.24 (49%)
Ships in 1-2 Business Days
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Product Specifications
- Other Name: RELAY, Headlamp/Fog Lamp/Turn Signal; Relay
- Warranty: This genuine part is guaranteed by GM's factory warranty.
Fits the following Vehicles:
- 2009-2012 Chevrolet Express | 1 TON CARGO EXPRESS, 1 TON CARGO SAVANA, 1 TON COMMERCIAL/RV CUTAWAY, 1 TON PASSENGER, 3/4 TON CARGO EXPRESS, 3/4 TON CARGO SAVANA, 3/4 TON PASSENGER EXPRESS, 3/4 TON PASSENGER SAVANA | 8 Cyl 6.6L Diesel
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Chevrolet Express RELAY ASM,WSW MOT *BLACK
Part Number: 13500126
$11.60 MSRP: $21.88
You Save: $10.28 (47%)
Ships in 1-3 Business Days
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Product Specifications
- Replaces: 19116058, 92181835, 92199311, 12135180, 12077866, 15328867, 19115082, 15393413
- Warranty: This genuine part is guaranteed by GM's factory warranty.
Fits the following Vehicles:
- 1996-2017 Chevrolet Express | 1 TON CARGO EXPRESS, 1 TON CARGO SAVANA, 1 TON COMMERCIAL/RECREATIONAL VEHICLE EXPRESS, 1 TON COMMERCIAL/RV CUTAWAY, 1 TON PASSENGER, 1/2 TON CARGO EXPRESS, 1/2 TON CARGO SAVANA, 1/2 TON PASSENGER EXPRESS, 1/2 TON PASSENGER SAVANA, 3/4 TON CARGO EXPRESS, 3/4 TON CARGO SAVANA, 3/4 TON PASSENGER EXPRESS, 3/4 TON PASSENGER SAVANA | 4 Cyl 2.8L Diesel, 6 Cyl 4.3L, 8 Cyl 4.8L, 8 Cyl 4.8L Flex, 8 Cyl 5.3L, 8 Cyl 5.3L Flex, 8 Cyl 6.0L, 8 Cyl 6.0L Flex, 8 Cyl 6.5L Diesel, 8 Cyl 6.6L Diesel, 8 Cyl 7.4L, 8 Cyl 8.1L
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Chevrolet Express Flasher,Hazard Lamp & Turn Signal Lamp
Part Number: 11516051
$43.81 MSRP: $85.40
You Save: $41.59 (49%)
Ships in 1-2 Business Days
ADD TO CART
Product Specifications
- Other Name: FLASHER, Chassis/Body Marker/Hazard; Flasher, Hazard Flasher, Turn Signal Flasher
- Warranty: This genuine part is guaranteed by GM's factory warranty.
Fits the following Vehicles:
- 1996-2001 Chevrolet Express | 1 TON CARGO EXPRESS, 1 TON PASSENGER, 1/2 TON CARGO EXPRESS, 1/2 TON PASSENGER EXPRESS, 3/4 TON CARGO EXPRESS, 3/4 TON PASSENGER EXPRESS | 6 Cyl 4.3L, 8 Cyl 5.0L, 8 Cyl 5.7L
View related parts
Chevrolet Express Relay,Multiuse
Part Number: 21997416
$22.44 MSRP: $42.34
You Save: $19.90 (47%)
Ships in 1-2 Business Days
ADD TO CART
Product Specifications
- Other Name: RELAY, Fuel Pump
- Replaces: 19115021, 19115563
- Warranty: This genuine part is guaranteed by GM's factory warranty.
Fits the following Vehicles:
- 2008-2009 Chevrolet Express | 1 TON CARGO EXPRESS, 1 TON COMMERCIAL/RV CUTAWAY, 1 TON PASSENGER, 1/2 TON CARGO EXPRESS, 1/2 TON PASSENGER EXPRESS, 3/4 TON CARGO EXPRESS, 3/4 TON PASSENGER EXPRESS | 6 Cyl 4.3L, 8 Cyl 4.8L, 8 Cyl 5.3L, 8 Cyl 6.0L, 8 Cyl 6.6L Diesel
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Chevrolet Express Relay Asm,Multiuse <See Guide/Contact Bf*Gray
Part Number: 19303153
$19.31 MSRP: $36.44
You Save: $17.13 (48%)
Ships in 1-2 Business Days
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Product Specifications
- Other Name: RELAY, Electronic Brake Control; Circuit Breaker, Relay
- Replaces: 12135197
- Warranty: This genuine part is guaranteed by GM's factory warranty.
Fits the following Vehicles:
- 2007-2009 Chevrolet Express | 1 TON CARGO EXPRESS, 1 TON COMMERCIAL/RV CUTAWAY, 1 TON PASSENGER, 1/2 TON CARGO EXPRESS, 1/2 TON PASSENGER EXPRESS, 3/4 TON CARGO EXPRESS, 3/4 TON PASSENGER EXPRESS | 6 Cyl 4.3L, 8 Cyl 4.8L, 8 Cyl 5.3L, 8 Cyl 5.3L Flex, 8 Cyl 6.0L, 8 Cyl 6.6L Diesel
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Chevrolet Express Relay Assembly, Fuel Pump
Part Number: 22899973
$70.53 MSRP: $133.09
You Save: $62.56 (48%)
Ships in 1-2 Business Days
ADD TO CART
Product Specifications
- Other Name: RELAY, Fuel Pump
- Warranty: This genuine part is guaranteed by GM's factory warranty.
Fits the following Vehicles:
- 2011-2015 Chevrolet Express | 1 TON COMMERCIAL/RV CUTAWAY | 8 Cyl 6.0L
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Chevrolet Express Relay
Part Number: 84095361
$5.28 MSRP: $8.00
You Save: $2.72 (34%)
Ships in 1-3 Business Days
ADD TO CART
Product Specifications
- Warranty: This genuine part is guaranteed by GM's factory warranty.
Fits the following Vehicles:
- 2003-2024 Chevrolet Express | 1 TON CARGO EXPRESS, 1 TON CARGO SAVANA, 1 TON COMMERCIAL/RV CUTAWAY, 1 TON PASSENGER, 1/2 TON CARGO EXPRESS, 1/2 TON CARGO SAVANA, 1/2 TON PASSENGER EXPRESS, 1/2 TON PASSENGER SAVANA, 3/4 TON CARGO EXPRESS, 3/4 TON CARGO SAVANA, 3/4 TON PASSENGER EXPRESS, 3/4 TON PASSENGER SAVANA, Van 3/4 Ton Cargo Express | 4 Cyl 2.8L Diesel, 6 Cyl 4.3L, 8 Cyl 4.8L, 8 Cyl 4.8L Flex, 8 Cyl 5.3L, 8 Cyl 5.3L Flex, 8 Cyl 6.0L, 8 Cyl 6.0L Flex, 8 Cyl 6.6L, 8 Cyl 6.6L Diesel
View related parts
Chevrolet Express Relay Assembly, Fuel Pump
Part Number: 22938003
$79.23 MSRP: $124.65
You Save: $45.42 (37%)
Ships in 1-3 Business Days
ADD TO CART
Product Specifications
- Other Name: RELAY, Fuel Pump
- Warranty: This genuine part is guaranteed by GM's factory warranty.
Fits the following Vehicles:
- 2011-2015 Chevrolet Express | 1 TON COMMERCIAL/RV CUTAWAY | 8 Cyl 6.0L
View related parts
Chevrolet Express Relay Kit,Glow Plug
Part Number: 12496472
Product Specifications
- Other Name: RELAY KIT, Voltage and Glow Plug; Glow Plug Controller, Relay
- Replaces: 12088560, 12135176
- Warranty: This genuine part is guaranteed by GM's factory warranty.
Fits the following Vehicles:
- 1996-2002 Chevrolet Express | 1 TON CARGO EXPRESS, 1 TON COMMERCIAL/RECREATIONAL VEHICLE EXPRESS, 1 TON PASSENGER, 3/4 TON CARGO EXPRESS, 3/4 TON PASSENGER EXPRESS | 8 Cyl 6.5L Diesel
View related parts
Chevrolet Express Relay Asm,Parking Lamp
Part Number: 12135151
Product Specifications
- Other Name: RELAY,Turn Signal & Cornering Lamp
- Warranty: This genuine part is guaranteed by GM's factory warranty.
Fits the following Vehicles:
- 1997-1999 Chevrolet Express | 1 TON CARGO EXPRESS, 1 TON COMMERCIAL/RECREATIONAL VEHICLE EXPRESS, 1 TON PASSENGER, 1/2 TON CARGO EXPRESS, 1/2 TON PASSENGER EXPRESS, 3/4 TON CARGO EXPRESS, 3/4 TON PASSENGER EXPRESS | 8 Cyl 6.5L Diesel
View related parts
Chevrolet Express Relay Asm,Accessory *Black
Part Number: 88986895
Product Specifications
- Other Name: RELAY, Voltage and Glow Plug; Relay
- Warranty: This genuine part is guaranteed by GM's factory warranty.
Fits the following Vehicles:
- 2003-2007 Chevrolet Express | 1 TON CARGO EXPRESS, 1 TON COMMERCIAL/RV CUTAWAY, 1 TON PASSENGER, 1/2 TON CARGO EXPRESS, 1/2 TON PASSENGER EXPRESS, 3/4 TON CARGO EXPRESS, 3/4 TON PASSENGER EXPRESS | 6 Cyl 4.3L, 8 Cyl 4.8L, 8 Cyl 5.3L, 8 Cyl 5.3L Flex, 8 Cyl 6.0L, 8 Cyl 6.6L Diesel
View related parts
Chevrolet Express Cable Asm Batt To Frame Grd Negative
Part Number: 8907034
Product Specifications
- Other Name: CABLE, Battery Negative and Engine Ground; Cable, Negative Cable
- Warranty: This genuine part is guaranteed by GM's factory warranty.
Fits the following Vehicles:
- 2000-2002 Chevrolet Express | 1 TON CARGO EXPRESS, 1 TON COMMERCIAL/RECREATIONAL VEHICLE EXPRESS, 1 TON PASSENGER, 3/4 TON CARGO EXPRESS, 3/4 TON PASSENGER EXPRESS | 8 Cyl 6.5L Diesel
View related parts
Chevrolet Express Flasher,Hazard Lamp & Turn Signal Lamp
Part Number: 12450072
Product Specifications
- Other Name: FLASHER, Chassis/Body Marker/Hazard; Flasher
- Warranty: This genuine part is guaranteed by GM's factory warranty.
Fits the following Vehicles:
- 2002 Chevrolet Express | 1 TON CARGO EXPRESS, 1 TON PASSENGER | 8 Cyl 5.7L

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1-20 of 25 Results

Chevrolet Express Relay

The Chevrolet Express Relay provides reliable switching to protect the climate and electrical circuits of the van by letting a low power signal control higher current elements. This tiny Relay receives commands from temperature and humidity sensors. It either completes or interrupts the circuit to the fans, compressors, and the blower motor. It prevents larger and more costly parts from running when they should not. Over the years, two main Relay styles have developed. The first, the ever familiar electromechanical Relay, is one that closes its contacts by means of an internal electromagnet. The second, the solid state Relay, achieves the same results only through semiconductor action and eliminating all the moving parts. Another type is the latching Relay, which stays in place after a short pulse. Any power loss will not change it. This feature is useful during starts or voltage dips. Despite all types serving the same function, the electromechanical variety is the greatly easy to troubleshoot, as you can simply listen for a click. Solid state units react the greatly quick and run cooler, while latching types consume the least ongoing power. Ensuring healthy operation of every Chevrolet system sensor and fitting the Express specific means stable cabin comfort free from needless part swaps, making the Chevrolet Express a reliable workhorse.

Each OEM Chevrolet Express Relay we offer is competitively priced and comes with the assurance of the manufacturer's warranty for the part. Furthermore, we guarantee the speedy delivery of your orders right to your doorstep. Our hassle-free return policy is also in place for your peace of mind.

Chevrolet Express Relay Parts Questions & Experts Answers

RELAY ASM,ACSRY TIME DELAY CUTOFF *GRAY
13500114
Q: How do relays function in electrical systems, and what steps should be taken to test and replace a defective relay on Chevrolet Express?
A:
Quite a number of electrical accessories in the vehicle use relays to pass current to the component, and if the relay is faulty, then the specified component will not function as expected. That fuse is more often found in the engine compartment fuse and relay box, while some are found in the several wiring harnesses underneath the instrument panel. The suspected faulty relay can be readily withdrawn and checked using a certain procedure or may be referred to a dealer service department or a competent repair shop and since the relays come as assemblies or assemblies of required relays that have become faulty, they must be replaced as a whole. Many of the relays utilized in these automobiles are termed as "ISO" relays and bear numerical suffixes referring to their typical circuit connections/uses; the ISO relays essentially have two classic types of terminal arrangements. In order to find out which wires are connected in which manner, the wiring diagram for the circuit in question must be consulted, and in the absence of this information the following facts may be helpful. The two terminals on the right are for the relay control circuit and connected to the relay coil while the other two are of the power circuit. In the energised state of the coil, the larger contacts of the power circuit are closed to allow energy to flow to the circuit loads. The control circuit is usually terminals 85 and 86; if the diode is present the 86 must go to battery positive and 85 to ground if the resistor is present either end of terminal 85 or 86 can be connected. Terminal 30 is used to link the unit to the battery voltage to the circuit loads while terminal 87 connects to the ground side of circuits. Continuity checks can be done on relay control coil using an ohmmeter by placing leads on the meter in correct polarity then switch the sides of lead to check for continuity in the other direction. If a resistor is present, the resistance should be equal whether in forward or reverse polarity, if a diode is present then resistance should be higher in forward polarity. Thus if there is an infinite resistance in normal as well as in the auxiliary circuit, it call for replacement of the relay. Once the relay is removed continuity should be tested between the power circuit terminals, there should be no continuity from terminal 30 to 87 when the circuit is de-energized. If a fused jumper wire is connected to terminal 86 and the positive battery terminal and another end of the relay to pin 85 to ground the relay should click. When the jumper wires are connected, there should be continuity between terminal number 30 and 87. Where any of the above tests fail, the relay should be replaced.