General Motors Co. knew more than a decade ago that loose ignition switches caused stalling on far more than its Chevrolet Cobalt and related small cars, redesigning switches in at least three high-volume car families between 2003 and 2006, according to recently disclosed company documents, reported The Wall Street Journal.

The auto maker didn’t recall the vehicles until last month, when it disclosed there were three deaths and 14 injuries in accidents involving 11 million vehicles under five different GM brands. Prompted by controversy about delayed recalls of the Cobalt, engineers tested a broader range of vehicles in the spring, and decided to order more recalls.

The disclosures, submitted to the National Highway Traffic Safety Administration, shed more light on the events that led to millions of GM vehicle recalls this year and could prompt more scrutiny by federal regulators. NHTSA fined the company $35 million, the maximum amount allowed by law, for its tardy response the Cobalt defects.

Separately, Fiat Chrysler Automobiles NV said it would recall up to 792,300 older Jeep Commander and Grand Cherokee vehicles over complaints that jarring the keys could unintentionally shut off the vehicles.

The latest Jeep recalls come amid heightened scrutiny of the role that switches play in controlling air bags. If a vehicle stalls because the ignition switch slips out of the run position, power could be cut to the brakes, steering and air bags, Fiat Chrysler warned.

At GM, an updated filing on its actions over time shows that a wider group of engineers than previously thought knew about ignition-switch troubles on many of its vehicles.

According to the disclosure, GM employees warned in 2005 and again in 2011 that ignition shut-offs presented a safety hazard in the Chevrolet Impala and Cadillac CTS. In 2013, an engineer assigned to investigate problems with unintended ignition shut-offs in the Cadillac CTS protested when other GM engineers refused to take action.

While the vehicles are larger than the Cobalt and related small cars, they were initially designed to use the same switch components approved by fired engineer Ray DeGiorgio. He was faulted in an internal report for approving a badly designed switch that became the foundation for ignition systems used in other families of vehicles.

All vehicles carrying that switch were subject to eight different tests earlier this year. If they failed one of the tests they were recalled, GM said.

Mr. DeGiorgio has shouldered much of the blame for GM’s ignition-switch controversy. Mr. DeGiorgio authorized a change to Cobalt ignition switches in 2006, and by doing so addressed a fundamental safety problem. Because ignition switches no longer malfunctioned, air bags were more likely to deploy in crashes. But he failed to document the change with a new part number, contributing to recall delays.

The internal GM report’s author, Chicago lawyer Anton Valukas, said that if more people had known, deaths could have been prevented. GM’s new disclosures, however, suggest the company failed to yield to several warnings dating back a decade.

In 2003, GM ordered the first in a series of changes over a few years to the designs of ignition switches used in five models—the Chevrolet Malibu, Pontiac Grand Am, Pontiac Grand Prix and Oldsmobile Alero cars; and the Cadillac SRX sport utility. The changes were implemented to decrease the risk of accidental shut offs, according to GM’s disclosure.

It isn’t clear from the regulatory filings whether GM engineers at this time viewed stalling as a safety problem.

These changes were modifications either done in the normal course of business or in response to some consumer complaints, a GM spokesman said. They never triggered a more intensive “field action” probe.

In 2003, GM ordered an increase in detent plunger force for 2004 Chevrolet Malibus, Grand Ams and Aleros—all members of the same platform family that underpinned small and midsize sedans. The detent plunger is a small piece of metal holding keys in position.

In 2004, GM engineers ordered changes to the detent plunger force on switches used in the Pontiac Grand Prix, a larger car belonging to yet another family of vehicles.

In 2006, the ignition switch design of the Cadillac SRX sport utility was changed to use a stronger detent plunger. In January 2010, GM issued a change in design of the keys used for Cadillac CTS sedans to a small hole from a wider slot.

This CTS modification is the same change GM engineers considered in 2005 for solving unintended engine shut-offs affecting Cobalts and Saturn Ions.

In October 2011, a GM employee driving a 2012 Cadillac CTS reported “a potential safety issue” after the car switched off when his knee bumped the key fob. A “CTS Current Product Improvement Team” reviewed the complaint and “decided not to seek a change in design unless the company received additional complaints about the condition,” GM’s chronology said.

But less than a year later another GM employee driving a 2012 CTS complained of stalls. A GM employee assigned to a “Red X” problem solving team, met with the employee who had filed the complaint. The employee who experienced the trouble was over 6 feet tall, and sat with his knee close to the key.The Red X team member drafted a “problem resolution tracking system” report, suggesting the key hole be changed back to a slot. In June of the following year, unidentified GM engineers decided to do nothing.The Red X investigation of the CTS, begun in May 2012, overlapped with a Red X investigation of why 2007 and 2008 Cobalts didn’t have the same frequency of air bag failures in accidents as older models did. The Cobalt Red X probe began in September 2012, according to the Valukas report.