P0700 Code: The One That Points at Another Code

OilAndMiles.com - Most OBD-II codes describe something that went wrong. This one describes a conversation. The module that runs your automatic transmission has its own memory and its own codes, and when it finds a fault it can't light a lamp itself, so it asks the engine computer to do it. P0700 is that request, written down.

Which means the useful code is the other one, and the federal complaint record shows how often it is there to be read.

What does a P0700 code mean?

The transmission module asked for the light, and stored the reason separately. An automatic transmission is run by its own computer, the transmission control module or TCM, which watches fluid pressure, gear ratios, speed sensors and the solenoids that do the shifting.

It has no lamp of its own. When it logs a fault it sets a flag the engine computer reads, and the engine computer stores P0700 and turns on the check engine light. The code's own name says so: transmission control system, MIL request, where MIL is the malfunction indicator lamp, the orange engine outline on your dashboard.

Some scan tools add a two-digit suffix. P0700-00 is the form GM owners search for most, and P0700-02 turns up in a Land Rover bulletin in the federal archive, stored in the transmission module. It's the same code either way, and we couldn't source what the two digits themselves encode.

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Why does P0700 almost never arrive alone?

Because it is a pointer, and the thing it points at is usually in the same scan. At least 140 of the 160 complaints name a second code beside it.

What the second code says, across the whole record:

• A pressure control solenoid, 56 times. P0747, P0776, P0796 and P2714 are four positions of the same kind of part, an electrically operated valve that sets the fluid pressure the transmission shifts with, and together they're the single most common thing behind a P0700 in this record.
• A speed or range sensor, 20 times. P0717, P0711 and P0705 cover the input speed sensor, the fluid temperature sensor and the gear range sensor.
• No conversation at all, 9 times. U0100 and U0073 are communication codes: the engine computer couldn't reach the transmission module. That's a wiring or a module question rather than a mechanical one.

Which cars actually report a P0700 code?

General Motors vehicles, by a wide margin, and for once the searching agrees. A hundred and sixty US complaints name this code across the 2010 to 2025 model years. A hundred and thirty-eight of them are GM: Chevrolet, GMC, Buick and Cadillac together.

The models are trucks first: the Chevrolet Silverado 1500 at 25 filings and the GMC Sierra 1500 at 16, then the Chevrolet Malibu at 9, the Equinox at 8 and the Tahoe at 6. Chevy badges also lead the searching for this code, and Subaru is the largest name outside GM with 12 filings.

What this record doesn't have is an era. The filings run from 1998 to 2026 with no bulge anywhere: eleven in 2010, sixteen in 2016, seventeen in 2021, fourteen in 2023. This isn't one generation's defect but a code any automatic transmission can set, and it has been set steadily for three decades.

Can you drive with a P0700 code?

Sometimes, and it's the second code that decides, not you. 37 of the 160 complaints describe limp mode, which is the transmission locking itself into one gear and capping your speed rather than keep shifting through whatever the second code names.

Thirty-five filings describe a car that wouldn't move at all, with no forward, no reverse, or stuck in gear. 9 filings describe both, so between them that is 63 of the 160 in which the car took the decision out of the driver's hands. Nothing in P0700 itself says which group a car is in.

Will a P0700 code fail an emissions test?

Yes, and clearing it first makes things worse. In states that read the computer, a stored code fails on its own, and the lamp being lit fails on its own in states that only look at the dashboard.

Erasing it doesn't produce a pass. It produces a car whose readiness monitors read not ready - those are the self-tests the computer works through as you drive, and a station wants them finished before it will accept a result. The erase also takes the second code, which was the one going to tell somebody what to fix.

What does it cost to fix a P0700 code?

Nothing, because there's nothing at that address to fix. The bill belongs to the second code, and the range is wide enough that guessing from P0700 is meaningless: a speed sensor and a rebuilt transmission are both on the other side of it.

18 of the 160 filings mention a rebuild or a replacement transmission, which is the expensive end and not the usual one. The figures we have researched for the repairs this code leads to are on the transmission slipping page and the transmission symptoms page, and a leak that starved the system is priced on the transmission fluid leak repair cost page.

What should you do about a P0700 code?

The first two of the 4 steps below cost nothing:

1. Write down every code on the scan, not just this one. P0700 beside P0747 is a pressure control solenoid. P0700 beside U0100 is a communication fault. P0700 beside P0717 is a speed sensor. The second code is the whole diagnosis, and it's free to read. One 2006 Jeep Commander owner's dealer did exactly that: the scan tool took them from P0700 to P2767, an input speed sensor.
2. Check the fluid before anything is ordered. Level and condition are the cheapest thing that changes how a transmission behaves, and on many vehicles there's no dipstick to check them with, so checking a sealed transmission is a job of its own.
3. Ask whether a bulletin covers your vehicle. The federal archive holds 34 manufacturer bulletins naming this code, and two of the most recent are quoted below.
4. Ask what the shop read, not what it suspects. A shop that has pulled the transmission module's own codes can name the component. A quote that names a rebuild without naming a second code has skipped the step that would have priced the job.

What if the scan shows only P0700?

It happens, and it's the case owners write about most unhappily. 20 of the 160 filings name no second code, and a GMC Sierra owner puts it plainly: I ran my scanner on my truck and code P0700 TCM was the only code showing. Three things are worth knowing:

• The second code may be in a module your scanner didn't ask. The transmission module stores its own codes, and not every tool requests them. So the thing to ask for is a scan of the transmission control module's own memory, not only the engine computer's, and to ask which modules the tool actually queried. A shop that can answer that has looked; one that can't has read the same screen you did.
• An intermittent fault sets the pointer and clears the detail. Several filings describe a light that comes and goes, and a code that is present one day and gone the next.
• This is where an owner's own checks end. Fluid pressure and solenoid operation are measured with equipment, not inspected by eye, and past this point the car has to be in front of somebody who has it.

US complaints naming P0700, by what else the owner filed with it: 160 complaints from the NHTSA complaint bulk download, file FLAT_CMPL, model years 2010 to 2025, deduplicated on the complaint number, read September 22, 2026. A filing can name more than one group.

What was filed beside P0700	Codes	Complaints
Pressure control solenoid	P0747, P0776, P0796, P2714	56
Speed or range sensor	P0717, P0711, P0705	20
No communication	U0100, U0073	9
No second code filed	P0700 alone	20

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Common questions

Asked most often

What does the P0700 code mean?

It means the transmission control module found a fault and asked the engine computer to turn on the check engine light. The code's full name is transmission control system, MIL request. The fault itself is stored as a separate code, and that second code is the one that names a part.

How do you fix a P0700 code?

You don't fix P0700. You read the code stored beside it and fix that. In the federal complaint record at least 140 of 160 filings name a second code, most often a pressure control solenoid, a speed sensor or a communication fault.

Can I drive with a P0700 code?

Sometimes, and the transmission may take the decision away from you. 37 of the 160 complaints describe limp mode, where the transmission locks into one gear and caps your speed, and 35 describe a car that wouldn't move at all. What decides it is the second code, not this one.

How much does it cost to fix a P0700 code?

There's no price for P0700 itself, and any quote attached to it alone is a guess. The bill belongs to the second code, and it runs from a speed sensor to a rebuilt transmission. 18 of the 160 filings mention a rebuild or a replacement, which is the expensive end rather than the usual one.

Is P0700 a transmission problem or an engine problem?

Transmission, in the sense that the transmission module raised it. But 9 of the filings pair it with U0100 or U0073, which are communication faults: the engine computer couldn't reach the transmission module at all. That's wiring or a module rather than anything mechanical inside the transmission.

Will a P0700 code clear itself?

The lamp can go out if the transmission module stops seeing the fault, and several filings describe exactly that coming and going. The fault doesn't clear itself. A code that returns is the module finding the same thing again.

Can a bad battery cause a P0700 code?

8 of the 160 filings mention a battery. In the five where one was replaced the code came back, and one owner fitted a new one on a forum's advice and the car then drove only in reverse. Where voltage really was involved, what got found was wiring. We couldn't source a battery causing it.

Does P0700 mean I need a new transmission?

Usually not. 18 of the 160 filings mention a rebuild or a replacement transmission, roughly one in nine, and a complaint record leans toward the worst outcomes because that's who files. The commonest second code is a pressure control solenoid, which is a part, not a transmission.

Can dirty transmission fluid cause a P0700 code?

Not as the thing anybody found. 7 of the 160 filings describe burnt fluid or metal in the pan, where the fluid reads as evidence of wear already done, and no filing names low fluid. Checking it is still worth doing first, because it costs nothing and rules something out.

What cars get P0700 most?

General Motors vehicles: 138 of the 160 US complaints naming this code are Chevrolet, GMC, Buick or Cadillac. The Chevrolet Silverado 1500 leads with 25 filings and the GMC Sierra 1500 follows with 16.

This page researched no prices of its own for the US market; the figures for the repairs this code leads to are on the transmission pages it links to, where they're sourced and dated. This article is general information, not advice about your specific vehicle, see the disclaimer.