B1984 OBD-II Trouble Code: Seat Switch Lumbar Inflate Circuit Failure

Our certified mechanics come to you · Get a fair and transparent estimate upfront

Red-stars EXCELLENT RATING ON

Cost of diagnosing the B1984 code

B1984 is a diagnostic trouble code (DTC) for "Seat Switch Lumbar Inflate Circuit Failure". This can happen for multiple reasons and a mechanic needs to diagnose the specific cause for this code to be triggered in your situation. Our certified mobile mechanics can come to your home or office to perform the Check Engine Light is on diagnostic inspection. Once we are able to diagnose the problem, you will be provided with an upfront quote for the recommended fix and receive $20.00 off as a credit towards the repair. All our repairs are backed by our 12-month / 12,000-mile warranty.

B1984 code definition

A B1984 trouble code indicates that the vehicle's Engine Control Unit (ECU) has detected an unspecified failure regarding the seat switch's lumbar inflate circuit.

What the B1984 code means

The lumbar circuits are so-named for relating to the lower region of the back. Certain luxury models of car will come equipped with these adjustable cushions which, when controlled, can help you sculpt the seat to suit your back. If a B1984 trouble code has been reported, the lumbar inflate circuit has suffered an unspecified failure. This will likely restrict the ability to inflate the cushion.

What causes the B1984 code?

Faulty components and electrical circuitry are most often to blame for an unspecified circuit failure. Some cases of the B1984 trouble code may be reported falsely by a malfunctioning ECU. Although this is a much rarer scenario than a failed circuit, it may be considered if all other plausible explanations have been exhausted.

What are the symptoms of the B1984 code?

A B1984 will restrict the lumbar control's ability to inflate (or harden) the lumbar cushion. In addition, the B1984 trouble code will come along with a stored trouble code and illuminated check engine lamp on the dashboard. These symptoms are diagnostic in nature, and are used to identify the issue in the first place.

How does a mechanic diagnose the B1984 code?

A mechanic may first diagnose the B1984 trouble code by reading the ECU with an OBD-II code scanner. The lumbar circuit may be found underneath the seat in question. From there, the lumbar circuit should be thoroughly inspected, checking for any apparent stops or damages relating to the electrical wiring or connectors. If all of the lumbar circuitry checks out, inspect the ECU for potential signs of malfunction.

Common mistakes when diagnosing the B1984 code

A B1984 is a body-related trouble codes. B-class codes can pose a risk of misinterpretation for home repairs, as one code can stand for different issues depending on the make and model of vehicle. Your OBD-II code reader may specify the issue for you. If you're not sure of the description, refer to the user manual or contact the manufacturer. Going through with repairs to an unrelated problem can be a major nuisance and risk wasted investment. All the while, the real problem will remain unaddressed.

How serious is the B1984 code?

Because of the pure luxury factor of a lumbar cushion, a B1984 trouble code shouldn't be seen as a serious problem, and can be repaired purely at the owner's discretion. Although no lumbar-related codes should be seen as serious concerns, the B1984 is slightly less serious than its B1985 ("cannot deflate lumbar") counterpart. This is because a highly inflated lumbar may prove more uncomfortable to a driver than a deflated cushion.

What repairs can fix the B1984 code?

If you have noted any wiring as being faulty, damaged, disconnected or otherwise problematic, it should be replaced, repaired, or rewired accordingly. In the event ECU has been proven faulty, it will need to be reprogrammed or replaced. Upon completing your repairs for the B1984 code, restart the vehicle to see if the code recurs. If the code returns upon restarting, you should return to the diagnostic phase of repair and see if you missed anything the first time around.

Additional comments for consideration regarding the B1984 code

You can purchase an independent lumbar cushion if you'd like to retain the lumbar support without making the repairs.

Need help with a B1984 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

trouble codes
B1984
OBD-II

No more waiting rooms! Our mechanics will come to you to diagnose and fix the B1984 code.

Get a $20 credit for the follow-up repair

Recent Check Engine Light is on Inspection reviews

Excellent Rating


YourMechanic Check Engine Light is on Inspection Service

Average Rating

4.8/5

Number of Reviews

5,736

Rating Summary
5,302
211
50
34
139
5,302
211
50
34
139

Nazareth

26 years of experience
168 reviews
Nazareth
26 years of experience
Mercedes-Benz CLA250 - Check Engine Light is on - Los Angeles, California
Polite and very professional! Nazareth quickly identified my car was suffering from low voltage issues and the battery was the problem. The reader was showing 8 volts hence why my car didn’t receive enough power to start, it needed 12v. My battery was 4 years old and never been changed. Thank you Nazareth!

Cornelius

17 years of experience
78 reviews
Cornelius
17 years of experience
Chevrolet Cobalt - Check Engine Light is on - Peachtree City, Georgia
He was very helpful with explaining what could lead to my check engine light being on. And helping clear my engine light.

Marco

28 years of experience
78 reviews
Marco
28 years of experience
Nissan Maxima - Check Engine Light is on - Highland, California
Marco did a great job of finding the source of the problem and his recommendations were greatly appreciated.

Juan

8 years of experience
128 reviews
Juan
8 years of experience
Chevrolet Tahoe - Check Engine Light is on - Altamonte Springs, Florida
Juan was on time for both appointments. He was knowledgeable and polite and I will most definitely be requesting him for my next steps based on the quote he provided me for other issues I need to address. Excellent customer service and top notch repair work!


More related articles

B1952 OBD-II Trouble Code: Seat Rear Up/Down Potentiometer Feedback Circuit Short To Battery
B1952 means a shorted circuit has been detected in relation to one of the rear seat's potentiometers, likely due to defective wiring.
P0445 OBD-II Trouble Code: Evaporative Emission Control System Purge Control Valve Circuit Shorted
Trouble code P0445 means the evaporative emission control system purge control valve has a problem.
P2646 OBD-II Trouble Code: 'A' Rocker Arm Actuator System Performance / Stuck Off Bank 1
P2646 code definition 'A' Rocker Arm Actuator System Performance or Stuck Off Bank 1 What the P2646 code means P2646 is an...

Related questions

I went to AAmco because my engine light was on! They did a diagnostic and came up with 2 codes. intake runner position sensor cir

Diagnostic Trouble Codes, such as the two codes that were retrieved at the first shop, cannot be used to "directly" condemn parts. Rather, these Codes are merely clues that are used to inform an actual diagnostic. But, short of an...

My Check Engine Light is on with a code for the engine control module

Unfortunately, without diagnosing the car using a scanning tool to download any potential trouble codes there is no way to tell what other codes may be causing this light to come on. There many different trouble codes that can also...

Malfunction Transmission light appeared on dashboard

Automatic transmissions can be tricky. Luckily, as odd as it seems, the fact your vehicle is setting a warning light is a good thing. This allow you to run a diagnostic scan for trouble codes, and will help narrow down...

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1 (855) 347-2779 · hi@yourmechanic.com