You need to know how they work before you go replacing part's . Test at the relay , is there B+ voltage on one side of the control coil of relay ? Is the BCM controlling the relay by supplying a ground ? There are videos on you tube on how relay's work an how to test them , Just remember the BCM controls a transistor inside to supply a ground to energize the relay ! The BCM has the ability to trouble shoot circuits an store DTC'S - diagnostic trouble codes . These code's will not turn on the check engine light .May turn on an other light on dash , a yellow wrench symbol ! Some of the thing's that could cause the high beams not to work are no B+ voltage at relay , no control by BCM !
You should have BCM scanned for trouble code's ,part's stores don't have the capability to do this . DTC B2580 01: Headlamp High Beam Control Circuit Short to Battery
DTC B2580 06: Headlamp High Beam Control Circuit Short to Ground or Open Do you know how to do electrical testing ? Headlamps Malfunction - High Beam
Ignition OFF, disconnect the high beam relay.
Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 87 and ground.
?‡' If the test lamp illuminates, test the control circuit for a short to voltage.
Verify that a test lamp illuminates between the B+ circuit terminal 30 and ground.
?‡' If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
Verify that a test lamp illuminates between the B+ circuit terminal 85 and ground.
?‡' If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
Disconnect the harness connector at the inoperative high beam headlamp.
Ignition OFF, scan tool OFF, exterior lamps OFF, test for less than 5 ohms between the ground circuit terminal B and ground.
?‡' If greater than the specified range, test the ground circuit for an open/high resistance.
Connect the harness connector at the inoperative high beam headlamp.
Connect a 20A fused jumper wire between the B+ circuit terminal 30 and the control circuit terminal 87. Verify the high beam headlamps illuminate.
?‡' If the high beam headlamps do not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the inoperative high beam headlamp.
Connect a test lamp between the B+ circuit terminal 85 and the control circuit terminal 86.
Command the High Beams ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
?‡' If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the BCM.
?‡' If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.
If all circuits test normal, test or replace the high beam relay.
Answers & Comments
You need to know how they work before you go replacing part's . Test at the relay , is there B+ voltage on one side of the control coil of relay ? Is the BCM controlling the relay by supplying a ground ? There are videos on you tube on how relay's work an how to test them , Just remember the BCM controls a transistor inside to supply a ground to energize the relay ! The BCM has the ability to trouble shoot circuits an store DTC'S - diagnostic trouble codes . These code's will not turn on the check engine light .May turn on an other light on dash , a yellow wrench symbol ! Some of the thing's that could cause the high beams not to work are no B+ voltage at relay , no control by BCM !
- Ignition OFF, disconnect the high beam relay.
- Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 87 and ground.
?‡'
- Verify that a test lamp illuminates between the B+ circuit terminal 30 and ground.
?‡'
- Verify that a test lamp illuminates between the B+ circuit terminal 85 and ground.
?‡'
- Disconnect the harness connector at the inoperative high beam headlamp.
- Ignition OFF, scan tool OFF, exterior lamps OFF, test for less than 5 ohms between the ground circuit terminal B and ground.
?‡'
- Connect the harness connector at the inoperative high beam headlamp.
- Connect a 20A fused jumper wire between the B+ circuit terminal 30 and the control circuit terminal 87. Verify the high beam headlamps illuminate.
?‡'
- Connect a test lamp between the B+ circuit terminal 85 and the control circuit terminal 86.
- Command the High Beams ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
?‡'
- If all circuits test normal, test or replace the high beam relay.
You should have BCM scanned for trouble code's ,part's stores don't have the capability to do this .
DTC B2580 01: Headlamp High Beam Control Circuit Short to Battery
DTC B2580 06: Headlamp High Beam Control Circuit Short to Ground or Open
Do you know how to do electrical testing ?
Headlamps Malfunction - High Beam
If the test lamp illuminates, test the control circuit for a short to voltage.
If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
If greater than the specified range, test the ground circuit for an open/high resistance.
If the high beam headlamps do not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the inoperative high beam headlamp.
If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the BCM.
?‡'
If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.
COULD BE FUSE MAYBE RELAY OR HEADLIGHT SWITCH.